diff --git a/code/datums/mutations.dm b/code/datums/mutations.dm
index 238c608dc99..adaefbf4ac4 100644
--- a/code/datums/mutations.dm
+++ b/code/datums/mutations.dm
@@ -280,22 +280,20 @@
 /datum/mutation/human/dwarfism
 
 	name = "Dwarfism"
-	quality = POSITIVE
-	get_chance = 15
-	lowest_value = 256 * 12
+	quality = MINOR_NEGATIVE
 	text_gain_indication = "<span class='notice'>Everything around you seems to grow..</span>"
 	text_lose_indication = "<span class='notice'>Everything around you seems to shrink..</span>"
 
 /datum/mutation/human/dwarfism/on_acquiring(mob/living/carbon/human/owner)
 	if(..())	return
 	owner.resize = 0.8
-	owner.ventcrawler = 1
+	owner.pass_flags = PASSTABLE
 	owner.visible_message("<span class='danger'>[owner] suddenly shrinks!</span>")
 
 /datum/mutation/human/dwarfism/on_losing(mob/living/carbon/human/owner)
 	if(..())	return
 	owner.resize = 1.25
-	owner.ventcrawler = 0
+	owner.pass_flags = 0
 	owner.visible_message("<span class='danger'>[owner] suddenly grows!</span>")
 
 /datum/mutation/human/clumsy