diff --git a/.eslintrc b/.eslintrc
index a4f11d858d19..baacdc920409 100644
--- a/.eslintrc
+++ b/.eslintrc
@@ -15,7 +15,7 @@
 		"Config": false, "Monitor": false, "toId": false, "Dex": false, "LoginServer": false,
 		"Users": false, "Punishments": false, "Rooms": false, "Verifier": false, "Chat": false,
 		"Tournaments": false, "Dnsbl": false, "Sockets": false, "TeamValidator": false,
-		"TeamValidatorAsync": false, "Ladders": false
+		"TeamValidatorAsync": false, "Ladders": false, "beforeAll": false, "afterAll": false
 	},
 	"extends": "eslint:recommended",
 	"rules": {
diff --git a/jest.config.js b/jest.config.js
new file mode 100644
index 000000000000..b79e17ceef65
--- /dev/null
+++ b/jest.config.js
@@ -0,0 +1,7 @@
+'use strict';
+
+module.exports = {
+	testEnvironment: 'node',
+	setupFilesAfterEnv: ['<rootDir>/test/main.js'],
+	testMatch: ['<rootDir>/test/simulator/**/*.js', '<rootDir>/test/application/*.js', '<rootDir>/test/chat-plugins/*.js', '<rootDir>/test/dev-tools/*.js'],
+};
diff --git a/package.json b/package.json
index e9652379d19a..72c616ac06cd 100644
--- a/package.json
+++ b/package.json
@@ -4,6 +4,7 @@
   "description": "The server for the Pokémon Showdown battle simulator",
   "version": "0.11.2",
   "dependencies": {
+    "jest": "^24.7.1",
     "probe-image-size": "^4.0.0",
     "sockjs": "0.3.19",
     "sucrase": "^3.10.1"
@@ -21,7 +22,7 @@
   "scripts": {
     "start": "node pokemon-showdown start",
     "build": "node build",
-    "test": "eslint --cache . && tslint --project . && node build && mocha && tsc",
+    "test": "eslint --cache . && tslint --project . && node build && jest && tsc",
     "tsc": "tsc",
     "lint": "eslint --cache ."
   },
@@ -63,7 +64,6 @@
     "@types/sockjs": "^0.3.31",
     "eslint": "^5.16.0",
     "husky": "^1.1.2",
-    "mocha": "^6.1.2",
     "tslint": "^5.15.0",
     "typescript": "^3.4.2"
   }
diff --git a/test/application/ladders-matchmaker.js b/test/application/ladders-matchmaker.js
index 6652a064c674..6d0c8ffba268 100644
--- a/test/application/ladders-matchmaker.js
+++ b/test/application/ladders-matchmaker.js
@@ -5,6 +5,9 @@ const assert = require('assert');
 global.Ladders = require('../../server/ladders');
 const {Connection, User} = require('../../dev-tools/users-utils');
 
+let p1, p2;
+let s1, s2;
+
 describe('Matchmaker', function () {
 	const FORMATID = 'gen7ou';
 	const addSearch = (player, rating = 1000, formatid = FORMATID) => {
@@ -19,64 +22,64 @@ describe('Matchmaker', function () {
 		return null;
 	};
 
-	before(function () {
+	beforeAll(function () {
 		clearInterval(Ladders.periodicMatchInterval);
 		Ladders.periodicMatchInterval = null;
 	});
 
 	beforeEach(function () {
-		this.p1 = new User(new Connection('127.0.0.1'));
-		this.p1.forceRename('Morfent', true);
-		this.p1.connected = true;
-		this.p1.team = 'Gengar||||lick||252,252,4,,,|||||';
-		Users.users.set(this.p1.userid, this.p1);
-
-		this.p2 = new User(new Connection('0.0.0.0'));
-		this.p2.forceRename('Mrofnet', true);
-		this.p2.connected = true;
-		this.p2.team = 'Gengar||||lick||252,252,4,,,|||||';
-		Users.users.set(this.p2.userid, this.p2);
+		p1 = new User(new Connection('127.0.0.1'));
+		p1.forceRename('Morfent', true);
+		p1.connected = true;
+		p1.team = 'Gengar||||lick||252,252,4,,,|||||';
+		Users.users.set(p1.userid, p1);
+
+		p2 = new User(new Connection('0.0.0.0'));
+		p2.forceRename('Mrofnet', true);
+		p2.connected = true;
+		p2.team = 'Gengar||||lick||252,252,4,,,|||||';
+		Users.users.set(p2.userid, p2);
 	});
 
 	afterEach(function () {
-		this.p1 = destroyPlayer(this.p1);
-		this.p2 = destroyPlayer(this.p2);
+		p1 = destroyPlayer(p1);
+		p2 = destroyPlayer(p2);
 	});
 
 	it('should add a search', function () {
-		let s1 = addSearch(this.p1);
+		let s1 = addSearch(p1);
 		assert.ok(Ladders.searches.has(FORMATID));
 
 		let formatSearches = Ladders.searches.get(FORMATID);
 		assert.ok(formatSearches instanceof Map);
 		assert.strictEqual(formatSearches.size, 1);
-		assert.strictEqual(s1.userid, this.p1.userid);
-		assert.strictEqual(s1.team, this.p1.team);
+		assert.strictEqual(s1.userid, p1.userid);
+		assert.strictEqual(s1.team, p1.team);
 		assert.strictEqual(s1.rating, 1000);
 	});
 
 	it('should matchmake users when appropriate', function () {
-		addSearch(this.p1);
-		addSearch(this.p2);
+		addSearch(p1);
+		addSearch(p2);
 		assert.strictEqual(Ladders.searches.get(FORMATID).size, 0);
 	});
 
 	it('should matchmake users within a reasonable rating range', function () {
-		addSearch(this.p1);
-		addSearch(this.p2, 2000);
+		addSearch(p1);
+		addSearch(p2, 2000);
 		assert.strictEqual(Ladders.searches.get(FORMATID).size, 2);
 	});
 
 	it('should cancel searches', function () {
-		addSearch(this.p1);
-		Ladders(FORMATID).cancelSearch(this.p1);
-		Ladders.cancelSearches(this.p2);
+		addSearch(p1);
+		Ladders(FORMATID).cancelSearch(p1);
+		Ladders.cancelSearches(p2);
 		assert.strictEqual(Ladders.searches.get(FORMATID).size, 0);
 	});
 
 	it('should periodically matchmake users when appropriate', function () {
-		addSearch(this.p1);
-		let s2 = addSearch(this.p2, 2000);
+		addSearch(p1);
+		let s2 = addSearch(p2, 2000);
 		assert.strictEqual(Ladders.searches.get(FORMATID).size, 2);
 
 		s2.rating = 1000;
@@ -85,59 +88,59 @@ describe('Matchmaker', function () {
 	});
 
 	it('should create a new battle room after matchmaking', function () {
-		assert.strictEqual(this.p1.games.size, 0);
-		addSearch(this.p1);
-		addSearch(this.p2);
-		assert.strictEqual(this.p1.games.size, 1);
-		for (const roomid of this.p1.games) {
+		assert.strictEqual(p1.games.size, 0);
+		addSearch(p1);
+		addSearch(p2);
+		assert.strictEqual(p1.games.size, 1);
+		for (const roomid of p1.games) {
 			assert.ok(Rooms(roomid).battle);
 		}
 	});
 
 	it('should cancel search on disconnect', function () {
-		addSearch(this.p1);
-		this.p1.onDisconnect(this.p1.connections[0]);
+		addSearch(p1);
+		p1.onDisconnect(p1.connections[0]);
 		assert.strictEqual(Ladders.searches.get(FORMATID).size, 0);
 	});
 
 	it('should cancel search on merge', function () {
-		addSearch(this.p1);
-		this.p2.merge(this.p1);
+		addSearch(p1);
+		p2.merge(p1);
 		assert.strictEqual(Ladders.searches.get(FORMATID).size, 0);
 	});
 
 	describe('#startBattle', function () {
 		beforeEach(function () {
-			this.s1 = addSearch(this.p1);
-			this.s2 = addSearch(this.p2);
+			s1 = addSearch(p1);
+			s2 = addSearch(p2);
 		});
 
 		afterEach(function () {
-			this.s1 = null;
-			this.s2 = null;
+			s1 = null;
+			s2 = null;
 		});
 
 		it('should prevent battles from starting if both players are identical', function () {
-			Object.assign(this.s2, this.s1);
+			Object.assign(s2, s1);
 			let room;
 			try {
-				room = Rooms.createBattle(FORMATID, {p1: this.p1, p2: this.p1, p1team: this.s1.team, p2team: this.s2.team, rated: 1000});
+				room = Rooms.createBattle(FORMATID, {p1: p1, p2: p1, p1team: s1.team, p2team: s2.team, rated: 1000});
 			} catch (e) {}
 			assert.strictEqual(room, undefined);
 		});
 
-		before(function () {
+		beforeAll(function () {
 			this.lockdown = Rooms.global.lockdown;
 			Rooms.global.lockdown = true;
 		});
 
-		after(function () {
+		afterAll(function () {
 			Rooms.global.lockdown = this.lockdown;
 			this.lockdown = null;
 		});
 
 		it('should prevent battles from starting if the server is in lockdown', function () {
-			let room = Rooms.createBattle(FORMATID, {p1: this.p1, p2: this.p2, p1team: this.s1.team, p2team: this.s2.team, rated: 1000});
+			let room = Rooms.createBattle(FORMATID, {p1: p1, p2: p2, p1team: s1.team, p2team: s2.team, rated: 1000});
 			assert.strictEqual(room, undefined);
 		});
 	});
diff --git a/test/application/sockets.js b/test/application/sockets.js
index 331c000074a7..bbd324e1eb4f 100644
--- a/test/application/sockets.js
+++ b/test/application/sockets.js
@@ -12,7 +12,7 @@ describe.skip('Sockets', function () {
 		})
 	);
 
-	before(function () {
+	beforeAll(function () {
 		cluster.settings.silent = true;
 		cluster.removeAllListeners('disconnect');
 	});
diff --git a/test/application/users.js b/test/application/users.js
index 1e59f13ba87f..95e0f30b6733 100644
--- a/test/application/users.js
+++ b/test/application/users.js
@@ -6,6 +6,8 @@ let userUtils = require('./../../dev-tools/users-utils');
 let Connection = userUtils.Connection;
 let User = userUtils.User;
 
+let connection;
+
 describe('Users features', function () {
 	describe('Users', function () {
 		describe('get', function () {
@@ -30,17 +32,17 @@ describe('Users features', function () {
 		describe('Connection', function () {
 			describe('#onDisconnect', function () {
 				beforeEach(function () {
-					this.connection = new Connection('127.0.0.1');
+					connection = new Connection('127.0.0.1');
 				});
 
 				it('should remove the connection from Users.connections', function () {
-					let connectionid = this.connection.id;
-					this.connection.destroy();
+					let connectionid = connection.id;
+					connection.destroy();
 					assert.strictEqual(Users.connections.has(connectionid), false);
 				});
 
 				it('should destroy any user on the connection as well', function () {
-					let user = new User(this.connection);
+					let user = new User(connection);
 					let {userid} = user;
 					user.disconnectAll();
 					user.destroy();
@@ -50,25 +52,25 @@ describe('Users features', function () {
 
 			describe('#joinRoom', function () {
 				beforeEach(function () {
-					this.connection = new Connection('127.0.0.1');
+					connection = new Connection('127.0.0.1');
 				});
 
 				afterEach(function () {
-					this.connection.destroy();
+					connection.destroy();
 				});
 
 				it('should join a room if not already present', function () {
-					this.connection.joinRoom(Rooms.lobby);
-					assert.ok(this.connection.inRooms.has('lobby'));
+					connection.joinRoom(Rooms.lobby);
+					assert.ok(connection.inRooms.has('lobby'));
 				});
 			});
 
 			describe('#leaveRoom', function () {
 				it('should leave a room that is present', function () {
-					this.connection = new Connection('127.0.0.1');
-					this.connection.joinRoom(Rooms.lobby);
-					this.connection.leaveRoom(Rooms.lobby);
-					assert.ok(!this.connection.inRooms.has('lobby'));
+					connection = new Connection('127.0.0.1');
+					connection.joinRoom(Rooms.lobby);
+					connection.leaveRoom(Rooms.lobby);
+					assert.ok(!connection.inRooms.has('lobby'));
 				});
 			});
 		});
diff --git a/test/chat-plugins/trivia.js b/test/chat-plugins/trivia.js
index b2a387bc444d..5b41eb5dc31c 100644
--- a/test/chat-plugins/trivia.js
+++ b/test/chat-plugins/trivia.js
@@ -28,8 +28,10 @@ function destroyUser(user) {
 	user.destroy();
 }
 
+let room, user, user2, user3, tarUser, game, player;
+
 describe('Trivia', function () {
-	before(function () {
+	beforeAll(function () {
 		// The trivia module cannot be loaded outside of this scope because
 		// it makes reference to global.Config in the modules outermost scope,
 		// which makes the module fail to be loaded. Within the scope of thess
@@ -41,282 +43,282 @@ describe('Trivia', function () {
 		NumberModeTrivia = trivia.NumberModeTrivia;
 
 		Rooms.global.addChatRoom('Trivia');
-		this.room = Rooms('trivia');
+		room = Rooms('trivia');
 	});
 
 	beforeEach(function () {
 		let questions = [{question: '', answers: ['answer'], category: 'ae'}];
-		this.user = makeUser('Morfent', new Connection('127.0.0.1'));
-		this.tarUser = makeUser('ReallyNotMorfent', new Connection('127.0.0.2'));
-		this.game = this.room.game = new Trivia(this.room, 'first', 'ae', 'short', questions);
+		user = makeUser('Morfent', new Connection('127.0.0.1'));
+		tarUser = makeUser('ReallyNotMorfent', new Connection('127.0.0.2'));
+		game = room.game = new Trivia(room, 'first', 'ae', 'short', questions);
 	});
 
 	afterEach(function () {
-		destroyUser(this.user);
-		destroyUser(this.tarUser);
-		if (this.room.game) {
-			clearTimeout(this.room.game.phaseTimeout);
-			this.room.game.phaseTimeout = null;
-			this.room.game.destroy();
+		destroyUser(user);
+		destroyUser(tarUser);
+		if (room.game) {
+			clearTimeout(room.game.phaseTimeout);
+			room.game.phaseTimeout = null;
+			room.game.destroy();
 		}
 	});
 
-	after(function () {
-		this.user = null;
-		this.tarUser = null;
-		this.room.destroy();
-		this.room = null;
+	afterAll(function () {
+		user = null;
+		tarUser = null;
+		room.destroy();
+		room = null;
 	});
 
 	it('should add new players', function () {
-		this.game.addPlayer(this.user);
-		assert.strictEqual(this.game.playerCount, 1);
+		game.addPlayer(user);
+		assert.strictEqual(game.playerCount, 1);
 	});
 
 	it('should not add a player if they have already joined', function () {
-		this.game.addPlayer(this.user);
-		this.game.addPlayer(this.user);
-		assert.strictEqual(this.game.playerCount, 1);
+		game.addPlayer(user);
+		game.addPlayer(user);
+		assert.strictEqual(game.playerCount, 1);
 	});
 
 	it('should not add a player if another one on the same IP has joined', function () {
-		this.game.addPlayer(this.user);
+		game.addPlayer(user);
 
 		let user2 = makeUser('Not Morfent', new Connection('127.0.0.1'));
-		this.game.addPlayer(user2);
+		game.addPlayer(user2);
 
-		assert.strictEqual(this.game.playerCount, 1);
+		assert.strictEqual(game.playerCount, 1);
 		destroyUser(user2);
 	});
 
 	it('should not add a player if another player had their username previously', function () {
-		let userid = this.user.userid;
-		let name = this.user.name;
-		this.game.addPlayer(this.user);
-		this.user.forceRename('Not Morfent', true);
-		this.user.prevNames[userid] = name;
+		let userid = user.userid;
+		let name = user.name;
+		game.addPlayer(user);
+		user.forceRename('Not Morfent', true);
+		user.prevNames[userid] = name;
 
 		let user2 = makeUser(name, new Connection('127.0.0.3'));
-		this.game.addPlayer(user2);
+		game.addPlayer(user2);
 
-		assert.strictEqual(this.game.playerCount, 1);
+		assert.strictEqual(game.playerCount, 1);
 		destroyUser(user2);
 	});
 
 	it('should not add a player if they were kicked from the game', function () {
-		this.game.kickedUsers.add(this.tarUser.userid);
-		this.game.addPlayer(this.tarUser);
-		assert.strictEqual(this.game.playerCount, 0);
+		game.kickedUsers.add(tarUser.userid);
+		game.addPlayer(tarUser);
+		assert.strictEqual(game.playerCount, 0);
 	});
 
 	it('should kick players from the game', function () {
-		this.game.addPlayer(this.tarUser);
-		this.game.kick(this.tarUser, this.user);
-		assert.strictEqual(this.game.playerCount, 0);
+		game.addPlayer(tarUser);
+		game.kick(tarUser, user);
+		assert.strictEqual(game.playerCount, 0);
 	});
 
 	it('should not kick players already kicked from the game', function () {
-		this.game.addPlayer(this.tarUser);
-		this.game.kick(this.tarUser, this.user);
-		let res = this.game.kick(this.tarUser, this.user);
+		game.addPlayer(tarUser);
+		game.kick(tarUser, user);
+		let res = game.kick(tarUser, user);
 		assert.strictEqual(typeof res, 'string');
 	});
 
 	it('should not kick users who were kicked under another name', function () {
-		this.game.addPlayer(this.tarUser);
-		this.game.kick(this.tarUser, this.user);
-
-		let userid = this.tarUser.userid;
-		let name = this.tarUser.name;
-		this.tarUser.forceRename('Not Morfent', true);
-		this.tarUser.prevNames[userid] = name;
-		this.game.addPlayer(this.tarUser);
-		assert.strictEqual(this.game.playerCount, 0);
+		game.addPlayer(tarUser);
+		game.kick(tarUser, user);
+
+		let userid = tarUser.userid;
+		let name = tarUser.name;
+		tarUser.forceRename('Not Morfent', true);
+		tarUser.prevNames[userid] = name;
+		game.addPlayer(tarUser);
+		assert.strictEqual(game.playerCount, 0);
 	});
 
 	it('should not add users who were kicked under another IP', function () {
-		this.game.addPlayer(this.tarUser);
-		this.game.kick(this.tarUser, this.user);
+		game.addPlayer(tarUser);
+		game.kick(tarUser, user);
 
-		let name = this.tarUser.name;
-		this.tarUser.resetName();
+		let name = tarUser.name;
+		tarUser.resetName();
 
 		let user2 = makeUser(name, new Connection('127.0.0.2'));
-		this.game.addPlayer(user2);
-		assert.strictEqual(this.game.playerCount, 0);
+		game.addPlayer(user2);
+		assert.strictEqual(game.playerCount, 0);
 		destroyUser(user2);
 	});
 
 	it('should not kick users that aren\'t players in the game', function () {
-		this.game.kick(this.tarUser, this.user);
-		assert.strictEqual(this.game.playerCount, 0);
+		game.kick(tarUser, user);
+		assert.strictEqual(game.playerCount, 0);
 	});
 
 	it('should make players leave the game', function () {
-		this.game.leave(this.user);
-		assert.strictEqual(this.game.players[this.user.userid], undefined);
+		game.leave(user);
+		assert.strictEqual(game.players[user.userid], undefined);
 	});
 
 	it('should not make users who are not players leave the game', function () {
-		this.game.leave(this.user);
-		let res = this.game.leave(this.user);
+		game.leave(user);
+		let res = game.leave(user);
 		assert.strictEqual(typeof res, 'string');
 	});
 
 	it('should verify answers correctly', function () {
-		this.game.askQuestion();
-		assert.strictEqual(this.game.verifyAnswer('answer'), true);
-		assert.strictEqual(this.game.verifyAnswer('anser'), true);
-		assert.strictEqual(this.game.verifyAnswer('not the right answer'), false);
+		game.askQuestion();
+		assert.strictEqual(game.verifyAnswer('answer'), true);
+		assert.strictEqual(game.verifyAnswer('anser'), true);
+		assert.strictEqual(game.verifyAnswer('not the right answer'), false);
 	});
 
 	it('should not throw when attempting to broadcast after the game has ended', function () {
-		this.game.destroy();
-		assert.doesNotThrow(() => this.game.broadcast('ayy', 'lmao'));
+		game.destroy();
+		assert.doesNotThrow(() => game.broadcast('ayy', 'lmao'));
 	});
 
-	context('marking player absence', function () {
+	describe('marking player absence', function () {
 		beforeEach(function () {
 			let questions = [null, null].fill({question: '', answers: ['answer'], category: 'ae'});
-			let game = new FirstModeTrivia(this.room, 'first', 'ae', 'short', questions);
-
-			this.user = makeUser('Morfent', new Connection('127.0.0.1'));
-			this.user2 = makeUser('user2', new Connection('127.0.0.2'));
-			this.user3 = makeUser('user3', new Connection('127.0.0.3'));
-
-			this.user.joinRoom(this.room);
-			game.addPlayer(this.user);
-			this.user2.joinRoom(this.room);
-			game.addPlayer(this.user2);
-			this.user3.joinRoom(this.room);
-			game.addPlayer(this.user3);
+			let game = new FirstModeTrivia(room, 'first', 'ae', 'short', questions);
+
+			user = makeUser('Morfent', new Connection('127.0.0.1'));
+			user2 = makeUser('user2', new Connection('127.0.0.2'));
+			user3 = makeUser('user3', new Connection('127.0.0.3'));
+
+			user.joinRoom(room);
+			game.addPlayer(user);
+			user2.joinRoom(room);
+			game.addPlayer(user2);
+			user3.joinRoom(room);
+			game.addPlayer(user3);
 			game.start();
 			game.askQuestion();
 			clearTimeout(game.phaseTimeout);
 			game.phaseTimeout = null;
 
-			this.game = this.room.game = game;
-			this.player = this.room.game.players[this.user.userid];
+			game = room.game = game;
+			player = room.game.players[user.userid];
 		});
 
 		afterEach(function () {
-			destroyUser(this.user);
-			destroyUser(this.user2);
-			destroyUser(this.user3);
-			if (this.room.game) {
-				clearTimeout(this.game.phaseTimeout);
-				this.game.phaseTimeout = null;
-				this.game.destroy();
+			destroyUser(user);
+			destroyUser(user2);
+			destroyUser(user3);
+			if (room.game) {
+				clearTimeout(game.phaseTimeout);
+				game.phaseTimeout = null;
+				game.destroy();
 			}
 		});
 
 		it('should mark a player absent on leave and pause the game', function () {
-			this.user.leaveRoom(this.room);
-			assert.strictEqual(this.player.isAbsent, true);
-			assert.strictEqual(this.game.phase, 'limbo');
-			assert.strictEqual(this.game.phaseTimeout, null);
+			user.leaveRoom(room);
+			assert.strictEqual(player.isAbsent, true);
+			assert.strictEqual(game.phase, 'limbo');
+			assert.strictEqual(game.phaseTimeout, null);
 		});
 
 		it('should unpause the game once enough players have returned', function () {
-			this.user.leaveRoom(this.room);
-			this.user.joinRoom(this.room);
-			assert.strictEqual(this.player.isAbsent, false);
-			assert.strictEqual(this.game.phase, 'question');
-			assert.ok(this.game.phaseTimeout);
+			user.leaveRoom(room);
+			user.joinRoom(room);
+			assert.strictEqual(player.isAbsent, false);
+			assert.strictEqual(game.phase, 'question');
+			assert.ok(game.phaseTimeout);
 		});
 	});
 
-	context('first mode', function () {
+	describe('first mode', function () {
 		beforeEach(function () {
 			let questions = [{question: '', answers: ['answer'], category: 'ae'}];
-			let game = new FirstModeTrivia(this.room, 'first', 'ae', 'short', questions);
+			let game = new FirstModeTrivia(room, 'first', 'ae', 'short', questions);
 
-			this.user = makeUser('Morfent', new Connection('127.0.0.1'));
-			this.user2 = makeUser('user2', new Connection('127.0.0.2'));
-			this.user3 = makeUser('user3', new Connection('127.0.0.3'));
+			user = makeUser('Morfent', new Connection('127.0.0.1'));
+			user2 = makeUser('user2', new Connection('127.0.0.2'));
+			user3 = makeUser('user3', new Connection('127.0.0.3'));
 
-			game.addPlayer(this.user);
-			game.addPlayer(this.user2);
-			game.addPlayer(this.user3);
+			game.addPlayer(user);
+			game.addPlayer(user2);
+			game.addPlayer(user3);
 			game.start();
 			game.askQuestion();
 
-			this.game = this.room.game = game;
-			this.player = game.players[this.user.userid];
+			game = room.game = game;
+			player = game.players[user.userid];
 		});
 
 		afterEach(function () {
-			destroyUser(this.user);
-			destroyUser(this.user2);
-			destroyUser(this.user3);
-			if (this.room.game) {
-				clearTimeout(this.game.phaseTimeout);
-				this.game.phaseTimeout = null;
-				this.game.destroy();
+			destroyUser(user);
+			destroyUser(user2);
+			destroyUser(user3);
+			if (room.game) {
+				clearTimeout(game.phaseTimeout);
+				game.phaseTimeout = null;
+				game.destroy();
 			}
 		});
 
 		it('should calculate player points correctly', function () {
-			let points = this.game.calculatePoints();
+			let points = game.calculatePoints();
 			assert.strictEqual(points, 5);
 		});
 
 		it('should allow users to answer questions correctly', function () {
-			this.game.answerQuestion('answer', this.user);
-			assert.strictEqual(this.player.correctAnswers, 1);
+			game.answerQuestion('answer', user);
+			assert.strictEqual(player.correctAnswers, 1);
 		});
 
 		it('should mark players who answer incorrectly', function () {
-			this.game.answerQuestion('not the right answer', this.user);
-			assert.strictEqual(this.player.correctAnswers, 0);
+			game.answerQuestion('not the right answer', user);
+			assert.strictEqual(player.correctAnswers, 0);
 		});
 
 		it('should only reward a player points once per question', function () {
-			this.game.answerQuestion('answer', this.user);
-			this.game.answerQuestion('answer', this.user);
-			assert.strictEqual(this.player.correctAnswers, 1);
+			game.answerQuestion('answer', user);
+			game.answerQuestion('answer', user);
+			assert.strictEqual(player.correctAnswers, 1);
 		});
 
 		it('should clear player answers if none answer correctly', function () {
-			this.game.answerQuestion('not the right answer', this.user);
-			this.game.tallyAnswers();
-			assert.strictEqual(this.player.answer, '');
+			game.answerQuestion('not the right answer', user);
+			game.tallyAnswers();
+			assert.strictEqual(player.answer, '');
 		});
 
 		it('should not give NaN points to correct responders', function () {
-			this.game.answerQuestion('answer', this.user);
-			this.game.tallyAnswers();
-			assert.ok(!isNaN(this.player.points));
+			game.answerQuestion('answer', user);
+			game.tallyAnswers();
+			assert.ok(!isNaN(player.points));
 		});
 	});
 
-	context('timer mode', function () {
+	describe('timer mode', function () {
 		beforeEach(function () {
 			let questions = [{question: '', answers: ['answer'], category: 'ae'}];
-			let game = new TimerModeTrivia(this.room, 'first', 'ae', 'short', questions);
+			let game = new TimerModeTrivia(room, 'first', 'ae', 'short', questions);
 
-			this.user = makeUser('Morfent', new Connection('127.0.0.1'));
-			this.user2 = makeUser('user2', new Connection('127.0.0.2'));
-			this.user3 = makeUser('user3', new Connection('127.0.0.3'));
+			user = makeUser('Morfent', new Connection('127.0.0.1'));
+			user2 = makeUser('user2', new Connection('127.0.0.2'));
+			user3 = makeUser('user3', new Connection('127.0.0.3'));
 
-			game.addPlayer(this.user);
-			game.addPlayer(this.user2);
-			game.addPlayer(this.user3);
+			game.addPlayer(user);
+			game.addPlayer(user2);
+			game.addPlayer(user3);
 			game.start();
 			game.askQuestion();
 
-			this.game = this.room.game = game;
-			this.player = game.players[this.user.userid];
+			game = room.game = game;
+			player = game.players[user.userid];
 		});
 
 		afterEach(function () {
-			destroyUser(this.user);
-			destroyUser(this.user2);
-			destroyUser(this.user3);
-			if (this.room.game) {
-				clearTimeout(this.game.phaseTimeout);
-				this.game.phaseTimeout = null;
-				this.game.destroy();
+			destroyUser(user);
+			destroyUser(user2);
+			destroyUser(user3);
+			if (room.game) {
+				clearTimeout(game.phaseTimeout);
+				game.phaseTimeout = null;
+				game.destroy();
 			}
 		});
 
@@ -325,33 +327,33 @@ describe('Trivia', function () {
 			let diff = -1;
 			for (let i = 6; i--;) {
 				diff += totalDiff / 5;
-				let points = this.game.calculatePoints(diff, totalDiff);
+				let points = game.calculatePoints(diff, totalDiff);
 				assert.strictEqual(points, i);
 			}
 		});
 
 		it('should set players as having answered correctly or incorrectly', function () {
-			this.game.answerQuestion('not the right answer', this.user);
-			assert.strictEqual(this.player.isCorrect, false);
-			this.game.answerQuestion('answer', this.user);
-			assert.strictEqual(this.player.isCorrect, true);
+			game.answerQuestion('not the right answer', user);
+			assert.strictEqual(player.isCorrect, false);
+			game.answerQuestion('answer', user);
+			assert.strictEqual(player.isCorrect, true);
 		});
 
 		it('should give points for correct answers', function () {
-			this.game.answerQuestion('answer', this.user);
-			this.game.tallyAnswers();
-			assert.strictEqual(this.player.correctAnswers, 1);
+			game.answerQuestion('answer', user);
+			game.tallyAnswers();
+			assert.strictEqual(player.correctAnswers, 1);
 		});
 
 		it('should choose the quicker answerer on tie', function (done) {
-			this.game.answerQuestion('answer', this.user);
+			game.answerQuestion('answer', user);
 			setImmediate(() => {
-				this.game.answerQuestion('answer', this.user2);
-				this.game.tallyAnswers();
+				game.answerQuestion('answer', user2);
+				game.tallyAnswers();
 
 				const hrtimeToNanoseconds = hrtime => hrtime[0] * 1e9 + hrtime[1];
-				let playerNs = hrtimeToNanoseconds(this.player.answeredAt);
-				let player2Ns = hrtimeToNanoseconds(this.game.players[this.user2.userid].answeredAt);
+				let playerNs = hrtimeToNanoseconds(player.answeredAt);
+				let player2Ns = hrtimeToNanoseconds(game.players[user2.userid].answeredAt);
 				assert.ok(playerNs <= player2Ns);
 
 				done();
@@ -359,46 +361,46 @@ describe('Trivia', function () {
 		});
 
 		it('should not give NaN points to correct responders', function () {
-			this.game.answerQuestion('answer', this.user);
-			this.game.tallyAnswers();
-			assert.ok(!isNaN(this.player.points));
+			game.answerQuestion('answer', user);
+			game.tallyAnswers();
+			assert.ok(!isNaN(player.points));
 		});
 	});
 
-	context('number mode', function () {
+	describe('number mode', function () {
 		beforeEach(function () {
 			let questions = [{question: '', answers: ['answer'], category: 'ae'}];
-			let game = new NumberModeTrivia(this.room, 'first', 'ae', 'short', questions);
+			let game = new NumberModeTrivia(room, 'first', 'ae', 'short', questions);
 
-			this.user = makeUser('Morfent', new Connection('127.0.0.1'));
-			this.user2 = makeUser('user2', new Connection('127.0.0.2'));
-			this.user3 = makeUser('user3', new Connection('127.0.0.3'));
+			user = makeUser('Morfent', new Connection('127.0.0.1'));
+			user2 = makeUser('user2', new Connection('127.0.0.2'));
+			user3 = makeUser('user3', new Connection('127.0.0.3'));
 
-			game.addPlayer(this.user);
-			game.addPlayer(this.user2);
-			game.addPlayer(this.user3);
+			game.addPlayer(user);
+			game.addPlayer(user2);
+			game.addPlayer(user3);
 			game.start();
 			game.askQuestion();
 
-			this.game = this.room.game = game;
-			this.player = game.players[this.user.userid];
+			game = room.game = game;
+			player = game.players[user.userid];
 		});
 
 		afterEach(function () {
-			destroyUser(this.user);
-			destroyUser(this.user2);
-			destroyUser(this.user3);
-			if (this.room.game) {
-				clearTimeout(this.game.phaseTimeout);
-				this.game.phaseTimeout = null;
-				this.game.destroy();
+			destroyUser(user);
+			destroyUser(user2);
+			destroyUser(user3);
+			if (room.game) {
+				clearTimeout(game.phaseTimeout);
+				game.phaseTimeout = null;
+				game.destroy();
 			}
 		});
 
 		it('should calculate points correctly', function () {
-			this.game.playerCount = 5;
+			game.playerCount = 5;
 			for (let i = 1; i <= 5; i++) {
-				assert.strictEqual(this.game.calculatePoints(i), 6 - i);
+				assert.strictEqual(game.calculatePoints(i), 6 - i);
 			}
 		});
 
@@ -406,21 +408,21 @@ describe('Trivia', function () {
 		// to that of timer mode.
 
 		it('should not give points for answering incorrectly', function () {
-			this.game.answerQuestion('not the right answer', this.user);
-			this.game.tallyAnswers();
-			assert.strictEqual(this.player.correctAnswers, 0);
+			game.answerQuestion('not the right answer', user);
+			game.tallyAnswers();
+			assert.strictEqual(player.correctAnswers, 0);
 		});
 
 		it('should give points for answering correctly', function () {
-			this.game.answerQuestion('answer', this.user);
-			this.game.tallyAnswers();
-			assert.strictEqual(this.player.correctAnswers, 1);
+			game.answerQuestion('answer', user);
+			game.tallyAnswers();
+			assert.strictEqual(player.correctAnswers, 1);
 		});
 
 		it('should not give NaN points to correct responders', function () {
-			this.game.answerQuestion('answer', this.user);
-			this.game.tallyAnswers();
-			assert.ok(!isNaN(this.player.points));
+			game.answerQuestion('answer', user);
+			game.tallyAnswers();
+			assert.ok(!isNaN(player.points));
 		});
 	});
 });
diff --git a/test/main.js b/test/main.js
index 24c8938c5158..9f7138e7acbb 100644
--- a/test/main.js
+++ b/test/main.js
@@ -5,8 +5,7 @@ const fs = require('fs');
 
 const noop = () => {};
 
-before('initialization', function () {
-	this.timeout(0); // Remove timeout limitation
+beforeAll(function () {
 	process.on('unhandledRejection', err => {
 		// I'd throw the err, but we have a heisenbug on our hands and I'd
 		// rather not have it screw with Travis in the interim
@@ -48,4 +47,4 @@ before('initialization', function () {
 	LoginServer.disabled = true;
 
 	Ladders.disabled = true;
-});
+}, 0);
diff --git a/test/mocha.opts b/test/mocha.opts
deleted file mode 100644
index 18275aa96fd0..000000000000
--- a/test/mocha.opts
+++ /dev/null
@@ -1,4 +0,0 @@
-test/main.js test/simulator/**/*.js test/application/*.js test/chat-plugins/*.js test/dev-tools/*.js
--R dot
--u bdd
---exit
diff --git a/test/simulator/abilities/arenatrap.js b/test/simulator/abilities/arenatrap.js
index 4c447ed5fdfb..838271f1de02 100644
--- a/test/simulator/abilities/arenatrap.js
+++ b/test/simulator/abilities/arenatrap.js
@@ -11,7 +11,6 @@ describe('Arena Trap', function () {
 	});
 
 	it('should prevent grounded Pokemon that are not immune to trapping from switching out normally', function () {
-		this.timeout(0);
 		battle = common.createBattle();
 		battle.setPlayer('p1', {team: [{species: "Dugtrio", ability: 'arenatrap', moves: ['snore', 'telekinesis', 'gravity']}]});
 		battle.setPlayer('p2', {team: [
@@ -53,5 +52,5 @@ describe('Arena Trap', function () {
 
 		assert.trapped(() => battle.makeChoices('', 'switch 4'), true); // Tornadus is trapped
 		assert.species(p2active[0], 'Tornadus');
-	});
+	}, 0);
 });
diff --git a/test/simulator/abilities/contrary.js b/test/simulator/abilities/contrary.js
index d97c0441ec71..3e897e2a8fcd 100644
--- a/test/simulator/abilities/contrary.js
+++ b/test/simulator/abilities/contrary.js
@@ -11,7 +11,6 @@ describe('Contrary', function () {
 	});
 
 	it('should invert relative stat changes', function () {
-		this.timeout(0);
 		battle = common.createBattle();
 		battle.setPlayer('p1', {team: [{species: "Spinda", ability: 'contrary', moves: ['superpower']}]});
 		battle.setPlayer('p2', {team: [{species: "Dragonite", ability: 'multiscale', moves: ['dragondance']}]});
@@ -19,7 +18,7 @@ describe('Contrary', function () {
 		battle.makeChoices('move superpower', 'move dragondance');
 		assert.statStage(contraryMon, 'atk', 1);
 		assert.statStage(contraryMon, 'def', 1);
-	});
+	}, 0);
 
 	it('should not invert absolute stat changes', function () {
 		battle = common.createBattle();
diff --git a/test/simulator/abilities/lightningrod.js b/test/simulator/abilities/lightningrod.js
index a7fb66b51cc7..94aae0ec797b 100644
--- a/test/simulator/abilities/lightningrod.js
+++ b/test/simulator/abilities/lightningrod.js
@@ -37,7 +37,6 @@ describe('Lightning Rod', function () {
 	});
 
 	it('should redirect single-target Electric-type attacks to the user if it is a valid target', function () {
-		this.timeout(3000);
 		battle = common.createBattle({gameType: 'triples'});
 		battle.setPlayer('p1', {team: [
 			{species: 'Manectric', ability: 'lightningrod', moves: ['sleeptalk']},
@@ -53,7 +52,7 @@ describe('Lightning Rod', function () {
 		assert.statStage(battle.p1.active[0], 'spa', 3);
 		assert.false.fullHP(battle.p1.active[2]);
 		assert.false.fullHP(battle.p2.active[0]);
-	});
+	}, 3000);
 
 	it('should redirect to the fastest Pokemon with the ability', function () {
 		battle = common.createBattle({gameType: 'doubles'});
diff --git a/test/simulator/abilities/pressure.js b/test/simulator/abilities/pressure.js
index 75f0a175221b..26e994a0ac9e 100644
--- a/test/simulator/abilities/pressure.js
+++ b/test/simulator/abilities/pressure.js
@@ -47,7 +47,6 @@ describe('Pressure', function () {
 	});
 
 	it('should deduct PP for each Pressure Pokemon targetted', function () {
-		this.timeout(3000);
 		battle = common.createBattle({gameType: 'triples'});
 		battle.setPlayer('p1', {team: [
 			{species: "Giratina", ability: 'pressure', moves: ['rest']},
@@ -63,10 +62,9 @@ describe('Pressure', function () {
 		assert.strictEqual(battle.p2.active[0].getMoveData(Dex.getMove('hail')).pp, 12);
 		assert.strictEqual(battle.p2.active[1].getMoveData(Dex.getMove('spikes')).pp, 28);
 		assert.strictEqual(battle.p2.active[2].getMoveData(Dex.getMove('rockslide')).pp, 13);
-	});
+	}, 3000);
 
 	it('should deduct PP for each opposing Pressure Pokemon when Snatch of Imprison are used', function () {
-		this.timeout(3000);
 		battle = common.createBattle({gameType: 'triples'});
 		battle.setPlayer('p1', {team: [
 			{species: "Giratina", ability: 'pressure', moves: ['rest']},
@@ -81,7 +79,7 @@ describe('Pressure', function () {
 		battle.makeChoices('move rest, move rest, move rest', 'move snatch, move imprison, move rest');
 		assert.strictEqual(battle.p2.active[0].getMoveData(Dex.getMove('snatch')).pp, 12);
 		assert.strictEqual(battle.p2.active[1].getMoveData(Dex.getMove('imprison')).pp, 12);
-	});
+	}, 3000);
 });
 
 describe('Pressure [Gen 4]', function () {
diff --git a/test/simulator/misc/random-teams.js b/test/simulator/misc/random-teams.js
index 4f6fd25c167b..e454fa5b1296 100644
--- a/test/simulator/misc/random-teams.js
+++ b/test/simulator/misc/random-teams.js
@@ -29,7 +29,6 @@ function isValidSet(gen, set) {
 describe(`Random Team generator`, function () {
 	for (const gen of ALL_GENS) {
 		it(`should successfully create valid Gen ${gen} teams`, function () {
-			this.timeout(0);
 			const generator = Dex.getTeamGenerator(`gen${gen}randombattle`);
 			if (generator.gen !== gen) return; // format doesn't exist for this gen
 
@@ -45,14 +44,13 @@ describe(`Random Team generator`, function () {
 					throw err;
 				}
 			}
-		});
+		}, 0);
 	}
 });
 
 describe(`Challenge Cup Team generator`, function () {
 	for (const gen of ALL_GENS) {
 		it(`should successfully create valid Gen ${gen} teams`, function () {
-			this.timeout(0);
 			const generator = Dex.getTeamGenerator(`gen${gen}challengecup`);
 			if (generator.gen !== gen) return; // format doesn't exist for this gen
 
@@ -68,14 +66,13 @@ describe(`Challenge Cup Team generator`, function () {
 					throw err;
 				}
 			}
-		});
+		}, 0);
 	}
 });
 
 describe(`Hackmons Cup Team generator`, function () {
 	for (const gen of ALL_GENS) {
 		it(`should successfully create valid Gen ${gen} teams`, function () {
-			this.timeout(0);
 			const generator = Dex.getTeamGenerator(`gen${gen}hackmonscup`);
 			if (generator.gen !== gen) return; // format doesn't exist for this gen
 
@@ -91,14 +88,13 @@ describe(`Hackmons Cup Team generator`, function () {
 					throw err;
 				}
 			}
-		});
+		}, 5000);
 	}
 });
 
 describe(`Factory sets`, function () {
 	for (const filename of ['bss-factory-sets', 'factory-sets']) {
 		it(`should have valid sets in ${filename}.json`, function () {
-			this.timeout(5000);
 			const setsJSON = require(`../../../data/${filename}.json`);
 
 			for (const type in setsJSON) {
diff --git a/test/simulator/misc/statusmoves.js b/test/simulator/misc/statusmoves.js
index 8d3d043e1417..50ad0d2d7ef3 100644
--- a/test/simulator/misc/statusmoves.js
+++ b/test/simulator/misc/statusmoves.js
@@ -33,8 +33,6 @@ describe('Most status moves', function () {
 	});
 
 	it('should fail when the opposing Pokemon is immune to the status effect it sets', function () {
-		this.timeout(0);
-
 		battle = common.createBattle();
 		battle.setPlayer('p1', {team: [{species: "Smeargle", ability: 'noguard', item: 'laggingtail', moves: ['thunderwave', 'willowisp', 'poisongas', 'toxic']}]});
 		battle.setPlayer('p2', {team: [
@@ -67,7 +65,7 @@ describe('Most status moves', function () {
 		battle.makeChoices('move toxic', 'move magnetrise');
 		assert.strictEqual(battle.p2.active[0].status, '');
 		assert.ok(battle.log[battle.lastMoveLine + 1].startsWith('|-immune|'));
-	});
+	}, 0);
 });
 
 describe('Poison-inflicting status moves [Gen 2]', function () {
diff --git a/test/simulator/moves/followme.js b/test/simulator/moves/followme.js
index a332135e2907..dbccc5661c57 100644
--- a/test/simulator/moves/followme.js
+++ b/test/simulator/moves/followme.js
@@ -11,8 +11,6 @@ describe('Follow Me', function () {
 	});
 
 	it('should redirect single-target moves towards it if it is a valid target', function () {
-		this.timeout(5000);
-
 		battle = common.createBattle({gameType: 'triples'});
 		battle.setPlayer('p1', {team: [
 			{species: 'Clefable', ability: 'unaware', moves: ['followme']},
@@ -32,7 +30,7 @@ describe('Follow Me', function () {
 		});
 		battle.makeChoices('move followme, move calmmind, move calmmind', 'move lowkick 2, move lowkick 2, move lowkick 2');
 		assert.strictEqual(hitCount, 2);
-	});
+	}, 5000);
 
 	it('should not redirect self-targetting moves', function () {
 		battle = common.createBattle({gameType: 'doubles'});
diff --git a/test/simulator/moves/ragepowder.js b/test/simulator/moves/ragepowder.js
index 38f154b12ac1..b87f57003ef7 100644
--- a/test/simulator/moves/ragepowder.js
+++ b/test/simulator/moves/ragepowder.js
@@ -12,8 +12,6 @@ describe('Rage Powder', function () {
 	});
 
 	it('should redirect single-target moves towards it if it is a valid target', function () {
-		this.timeout(5000);
-
 		battle = common.createBattle({gameType: 'triples'});
 		battle.setPlayer('p1', {team: [
 			{species: 'Amoonguss', ability: 'overcoat', item: 'safetygoggles', moves: ['ragepowder']},
@@ -42,7 +40,7 @@ describe('Rage Powder', function () {
 		assert.strictEqual(hitCount[0], 2);
 		assert.strictEqual(hitCount[1], 1);
 		assert.strictEqual(hitCount[2], 0);
-	});
+	}, 5000);
 
 	it('should not affect Pokemon with Powder immunities', function () {
 		battle = common.createBattle({gameType: 'triples'});