diff --git a/code/modules/bitrunning/server/threats.dm b/code/modules/bitrunning/server/threats.dm
index 66a96d9971f..59d5646eca1 100644
--- a/code/modules/bitrunning/server/threats.dm
+++ b/code/modules/bitrunning/server/threats.dm
@@ -156,7 +156,7 @@
 /// Removes any invalid candidates from the list
 /obj/machinery/quantum_server/proc/validate_mutation_candidates()
 	for(var/datum/weakref/creature_ref as anything in mutation_candidate_refs)
-		var/mob/living/creature = creature_ref.resolve()
+		var/mob/living/creature = creature_ref?.resolve() // BUBBER EDIT - REF CHECK for RUNTIME AVOIDANCE
 		if(isnull(creature) || creature.mind)
 			mutation_candidate_refs.Remove(creature_ref)