diff --git a/code/__DEFINES/xeno.dm b/code/__DEFINES/xeno.dm
index 935f58f69c..c77dac05fc 100644
--- a/code/__DEFINES/xeno.dm
+++ b/code/__DEFINES/xeno.dm
@@ -662,7 +662,6 @@
 #define FIRE_IMMUNITY_NO_DAMAGE			(1<<0)
 #define FIRE_IMMUNITY_NO_IGNITE			(1<<1)
 #define FIRE_IMMUNITY_XENO_FRENZY		(1<<2)
-#define FIRE_VULNERABILITY				(1<<3)
 
 #define FIRE_MULTIPLIER_BASE	 	1
 #define FIRE_MULTIPLIER_LOW		 	1.25
diff --git a/code/modules/mob/living/carbon/xenomorph/castes/Boiler.dm b/code/modules/mob/living/carbon/xenomorph/castes/Boiler.dm
index 092dae00d6..2651137a80 100644
--- a/code/modules/mob/living/carbon/xenomorph/castes/Boiler.dm
+++ b/code/modules/mob/living/carbon/xenomorph/castes/Boiler.dm
@@ -22,7 +22,6 @@
 	acid_level = 3
 	caste_luminosity = 2
 	spit_types = list(/datum/ammo/xeno/boiler_gas, /datum/ammo/xeno/boiler_gas/acid)
-	fire_immunity = FIRE_VULNERABILITY
 	// 3x fire damage
 	fire_vulnerability_mult = FIRE_MULTIPLIER_DEADLY
 
diff --git a/code/modules/mob/living/carbon/xenomorph/castes/Crusher.dm b/code/modules/mob/living/carbon/xenomorph/castes/Crusher.dm
index 9922858264..ae7243af9f 100644
--- a/code/modules/mob/living/carbon/xenomorph/castes/Crusher.dm
+++ b/code/modules/mob/living/carbon/xenomorph/castes/Crusher.dm
@@ -25,7 +25,7 @@
 	evolution_allowed = FALSE
 	deevolves_to = list(XENO_CASTE_WARRIOR)
 	caste_desc = "A huge tanky xenomorph."
-	fire_intensity_resistance = 40
+	fire_intensity_resistance = 10
 	fire_vulnerability_mult = 0.25
 
 	minimap_icon = "crusher"
diff --git a/code/modules/mob/living/carbon/xenomorph/life.dm b/code/modules/mob/living/carbon/xenomorph/life.dm
index f1f02e47a7..6ea3b699dc 100644
--- a/code/modules/mob/living/carbon/xenomorph/life.dm
+++ b/code/modules/mob/living/carbon/xenomorph/life.dm
@@ -83,10 +83,7 @@
 		G.die()
 		drop_inv_item_on_ground(G)
 	if(!caste || !(caste.fire_immunity & FIRE_IMMUNITY_NO_DAMAGE) || fire_reagent.fire_penetrating)
-		if(caste.fire_immunity & FIRE_VULNERABILITY && caste.fire_vulnerability_mult != 1)
-			apply_damage(PASSIVE_BURN_DAM_CALC(fire_reagent.intensityfire, fire_reagent.durationfire, fire_stacks) * caste.fire_vulnerability_mult, BURN)
-		else
-			apply_damage(armor_damage_reduction(GLOB.xeno_fire, PASSIVE_BURN_DAM_CALC(fire_reagent.intensityfire, fire_reagent.durationfire, fire_stacks)), BURN)
+		apply_damage(armor_damage_reduction(GLOB.xeno_fire, PASSIVE_BURN_DAM_CALC(fire_reagent.intensityfire, fire_reagent.durationfire, fire_stacks) * caste.fire_vulnerability_mult), BURN)
 		INVOKE_ASYNC(src, TYPE_PROC_REF(/mob, emote), pick("roar", "needhelp"))
 
 #undef PASSIVE_BURN_DAM_CALC
diff --git a/code/modules/mob/living/carbon/xenomorph/xeno_defines.dm b/code/modules/mob/living/carbon/xenomorph/xeno_defines.dm
index a74fa74138..f2e287b6fc 100644
--- a/code/modules/mob/living/carbon/xenomorph/xeno_defines.dm
+++ b/code/modules/mob/living/carbon/xenomorph/xeno_defines.dm
@@ -101,7 +101,7 @@
 	var/caste_luminosity = 0
 
 	/// if fire_immunity is set to be vulnerable, how much will fire damage be multiplied. Defines in xeno.dm
-	var/fire_vulnerability_mult = 0
+	var/fire_vulnerability_mult = 1
 
 	var/burrow_cooldown = 5 SECONDS
 	var/tunnel_cooldown = 100