Bodies Can No Longer Be Easily Superheated (#376)

code/__DEFINES/atmospherics/atmos_mob_interaction.dm

@@ -78,6 +78,9 @@
 /// The temperature the blue icon is displayed.
 #define BODYTEMP_COLD_WARNING_3 (BODYTEMP_COLD_DAMAGE_LIMIT - 150) //120k
 
+/// Beyond this temperature, being on fire will increase body temperature by less and less
+#define BODYTEMP_FIRE_TEMP_SOFTCAP 1200
+
 /// The amount of pressure damage someone takes is equal to (pressure / HAZARD_HIGH_PRESSURE)*PRESSURE_DAMAGE_COEFFICIENT, with the maximum of MAX_PRESSURE_DAMAGE
 #define PRESSURE_DAMAGE_COEFFICIENT 2
 #define MAX_HIGH_PRESSURE_DAMAGE 2

code/datums/status_effects/debuffs/fire_stacks.dm

@@ -197,14 +197,19 @@
 	var/mob/living/carbon/human/victim = owner
 	var/thermal_protection = victim.get_thermal_protection()
 
-	if(thermal_protection >= FIRE_IMMUNITY_MAX_TEMP_PROTECT && !no_protection)
-		return
+	if(!no_protection)
+		if(thermal_protection >= FIRE_IMMUNITY_MAX_TEMP_PROTECT)
+			return
+		if(thermal_protection >= FIRE_SUIT_MAX_TEMP_PROTECT)
+			victim.adjust_bodytemperature(5.5 * delta_time)
+			return
 
-	if(thermal_protection >= FIRE_SUIT_MAX_TEMP_PROTECT && !no_protection)
-		victim.adjust_bodytemperature(5.5 * delta_time)
-		return
+	var/amount_to_heat = (BODYTEMP_HEATING_MAX + (stacks * 12)) * 0.5 * delta_time
+	if(owner.bodytemperature > BODYTEMP_FIRE_TEMP_SOFTCAP)
+		// Apply dimishing returns upon temp beyond the soft cap
+		amount_to_heat = amount_to_heat ** (BODYTEMP_FIRE_TEMP_SOFTCAP / owner.bodytemperature)
 
-	victim.adjust_bodytemperature((BODYTEMP_HEATING_MAX + (stacks * 12)) * 0.5 * delta_time)
+	victim.adjust_bodytemperature(amount_to_heat)
 	victim.add_mood_event("on_fire", /datum/mood_event/on_fire)
 	victim.mind?.add_memory(MEMORY_FIRE, list(DETAIL_PROTAGONIST = victim), story_value = STORY_VALUE_OKAY)