acid well changes and minor grenade code (#12900)

* acid well changes and minor grenade changes

* cleaner code/no redudancy

* 2 charge removal of stickies

* adds smoke, cleanup

* code clean up

code/game/objects/items/explosives/grenades/marines.dm

@@ -98,7 +98,6 @@
 
 /obj/item/explosive/grenade/sticky/prime()
 	if(stuck_to)
-		stuck_to.cut_overlay(saved_overlay)
 		clean_refs()
 	return ..()
 
@@ -107,6 +106,7 @@
 
 ///Cleans references to prevent hard deletes.
 /obj/item/explosive/grenade/sticky/proc/clean_refs()
+	stuck_to.cut_overlay(saved_overlay)
 	SIGNAL_HANDLER
 	UnregisterSignal(stuck_to, COMSIG_PARENT_QDELETING)
 	stuck_to = null
@@ -124,7 +124,6 @@
 	flame_radius(0.5, get_turf(src))
 	playsound(loc, "incendiary_explosion", 35)
 	if(stuck_to)
-		stuck_to.cut_overlay(saved_overlay)
 		clean_refs()
 	qdel(src)
 
@@ -143,6 +142,7 @@
 	T.ignite(25, 25)
 
 /obj/item/explosive/grenade/sticky/trailblazer/clean_refs()
+	stuck_to.cut_overlay(saved_overlay)
 	UnregisterSignal(stuck_to, COMSIG_MOVABLE_MOVED)
 	return ..()
 

code/modules/xenomorph/xeno_structures.dm

@@ -600,6 +600,17 @@ TUNNEL
 
 	var/datum/effect_system/smoke_spread/xeno/acid/acid_smoke
 
+	if(charges >= 2)
+		for(var/obj/item/explosive/grenade/sticky/sticky_bomb in stepper.contents)
+			sticky_bomb.clean_refs()
+			qdel(sticky_bomb)
+		charges -= 2
+		acid_smoke = new(get_turf(stepper))
+		acid_smoke.set_up(1, src)
+		acid_smoke.start()
+		update_icon()
+		if(!charges)
+			return
 	if(isxeno(stepper))
 		if(!(stepper.on_fire))
 			return