Some adjustments, following suggestions in the PR discussion.

code/datums/mutations.dm

@@ -19,7 +19,7 @@
 	var/layer_used = MUTATIONS_LAYER //which mutation layer to use
 	var/list/species_allowed = list() //to restrict mutation to only certain species
 	var/health_req //minimum health required to acquire the mutation
-	var/limb_req //required limbs to qcquire this mutation
+	var/limb_req //required limbs to acquire this mutation
 	var/time_coeff = 1 //coefficient for timed mutations
 
 /datum/mutation/human/proc/force_give(mob/living/carbon/human/owner)

code/game/gamemodes/changeling/powers/fleshmend.dm

@@ -31,7 +31,7 @@
 			H.restore_blood()
 			H.remove_all_embedded_objects()
 			if(H.get_missing_limbs())
-				playsound(get_turf(H), 'sound/effects/blobattack.ogg', 30, 1)
+				playsound(user, 'sound/magic/Demon_consume.ogg', 50, 1)
 				H.visible_message("<span class='warning'>[user]'s missing limbs reform, making a loud, grotesque sound!</span>", "<span class='userdanger'>Your limbs regrow, making a loud, crunchy sound and giving you great pain!</span>", "<span class='italics'>You hear organic matter ripping and tearing!</span>")
 				H.emote("scream")
 				H.regenerate_limbs(1)

code/game/gamemodes/changeling/powers/mutations.dm

@@ -48,7 +48,7 @@
 	else
 		limb_regen = user.regenerate_limb("r_arm", 1)
 	if(limb_regen)
-		user.visible_message("<span class='warning'>[user]'s missing arm reform, making a loud, grotesque sound!</span>", "<span class='userdanger'>Your arm regrow, making a loud, crunchy sound and giving you great pain!</span>", "<span class='italics'>You hear organic matter ripping and tearing!</span>")
+		user.visible_message("<span class='warning'>[user]'s missing arm reforms, making a loud, grotesque sound!</span>", "<span class='userdanger'>Your arm regrow, making a loud, crunchy sound and giving you great pain!</span>", "<span class='italics'>You hear organic matter ripping and tearing!</span>")
 		user.emote("scream")
 	var/obj/item/W = new weapon_type(user)
 	user.put_in_hands(W)

code/game/objects/items/stacks/medical.dm

@@ -34,7 +34,7 @@
 		var/mob/living/carbon/human/H = M
 		affecting = H.get_bodypart(check_zone(user.zone_selected))
 		if(!affecting) //Missing limb?
-			user << "<span class='warning'>[H] doesn't have [parse_zone(user.zone_selected)]!</span>"
+			user << "<span class='warning'>[H] doesn't have \a [parse_zone(user.zone_selected)]!</span>"
 			return
 		if(stop_bleeding)
 			if(H.bleedsuppress)
@@ -79,7 +79,7 @@
 		var/mob/living/carbon/human/H = M
 		affecting = H.get_bodypart(check_zone(user.zone_selected))
 		if(!affecting) //Missing limb?
-			user << "<span class='warning'>[H] doesn't have [parse_zone(user.zone_selected)]!</span>"
+			user << "<span class='warning'>[H] doesn't have \a [parse_zone(user.zone_selected)]!</span>"
 			return
 		if(stop_bleeding)
 			if(!H.bleedsuppress) //so you can't stack bleed suppression

code/modules/admin/verbs/debug.dm

@@ -362,7 +362,7 @@ var/list/TYPES_SHORTCUTS = list(
 	/obj/machinery/portable_atmospherics = "PORT_ATMOS",
 	/obj/item/mecha_parts/mecha_equipment/weapon/ballistic/launcher/missile_rack = "MECHA_MISSILE_RACK",
 	/obj/item/mecha_parts/mecha_equipment = "MECHA_EQUIP",
-	/obj/item/organ = "ORGAN_INT",
+	/obj/item/organ = "ORGAN",
 )
 
 var/global/list/g_fancy_list_of_types = null

code/modules/mob/living/carbon/human/human.dm

@@ -148,7 +148,8 @@
 
 	take_overall_damage(b_loss,f_loss)
 	//attempt to dismember bodyparts
-	for(var/obj/item/bodypart/BP in bodyparts)
+	for(var/X in bodyparts)
+		var/obj/item/bodypart/BP = X
 		if(prob(50/severity) && BP.body_zone != "head" && BP.body_zone != "chest")
 			BP.dismember()
 	..()

code/modules/mob/living/carbon/human/species.dm

@@ -193,7 +193,7 @@
 	H.remove_overlay(HAIR_LAYER)
 
 	var/obj/item/bodypart/head/HD = H.get_bodypart("head")
-	if(!HD || HD.status == ORGAN_ROBOTIC) //Decapitated or robotic head
+	if(!HD) //Decapitated
 		return
 
 	if(H.disabilities & HUSK)
@@ -488,8 +488,8 @@
 		if(!(type in I.species_exception))
 			return 0
 
-	var/R = H.has_right_hand(1)
-	var/L = H.has_left_hand(1)
+	var/R = H.has_right_hand()
+	var/L = H.has_left_hand()
 	var/num_arms = H.get_num_arms()
 	var/num_legs = H.get_num_legs()
 

code/modules/mob/mob_helpers.dm

@@ -28,21 +28,28 @@
 	return zone
 
 
-/proc/ran_zone(zone, probability = 80, list/exceptions)
+/proc/ran_zone(zone, probability = 80)
+
 	zone = check_zone(zone)
 
-	if(!islist(exceptions))
-		exceptions = list()
-
-	if(prob(probability) && !locate(zone) in exceptions)
+	if(prob(probability))
 		return zone
 
-	var/list/choices = list("head", "chest", "l_arm", "r_arm", "l_leg", "r_leg")
-	choices = difflist(choices, exceptions) //Strip away zones to ignore
-	if(!choices.len)
-		return 0
+	var/t = rand(1, 18) // randomly pick a different zone, or maybe the same one
+	switch(t)
+		if(1)
+			return "head"
+		if(2)
+			return "chest"
+		if(3 to 6)
+			return "l_arm"
+		if(7 to 10)
+			return "r_arm"
+		if(11 to 14)
+			return "l_leg"
+		if(15 to 18)
+			return "r_leg"
 
-	zone = pick(choices) //Pick a random zone
 	return zone
 
 /proc/above_neck(zone)

code/modules/surgery/bodyparts/bodyparts.dm

@@ -1,6 +1,7 @@
 
 /obj/item/bodypart
 	name = "limb"
+	desc = "why is it detached..."
 	var/mob/living/carbon/human/owner = null
 	var/status = ORGAN_ORGANIC
 	var/body_zone //"chest", "l_arm", etc , used for def_zone
@@ -264,7 +265,7 @@
 
 /obj/item/bodypart/chest
 	name = "chest"
-	desc = "why is it detached..."
+	desc = "It's impolite to stare at a person's chest."
 	icon_state = "chest"
 	max_damage = 200
 	body_zone = "chest"
@@ -280,7 +281,6 @@
 
 /obj/item/bodypart/l_arm
 	name = "left arm"
-	desc = "why is it detached..."
 	icon_state = "l_arm"
 	max_damage = 75
 	body_zone ="l_arm"
@@ -290,7 +290,6 @@
 
 /obj/item/bodypart/r_arm
 	name = "right arm"
-	desc = "why is it detached..."
 	icon_state = "r_arm"
 	max_damage = 75
 	body_zone = "r_arm"
@@ -300,7 +299,6 @@
 
 /obj/item/bodypart/l_leg
 	name = "left leg"
-	desc = "why is it detached..."
 	icon_state = "l_leg"
 	max_damage = 75
 	body_zone = "l_leg"
@@ -310,7 +308,6 @@
 
 /obj/item/bodypart/r_leg
 	name = "right leg"
-	desc = "why is it detached..."
 	icon_state = "r_leg"
 	max_damage = 75
 	body_zone = "r_leg"

code/modules/surgery/bodyparts/dismemberment.dm

@@ -15,7 +15,7 @@
 	var/direction = pick(cardinal)
 	var/t_range = rand(2,max(throw_range/2, 2))
 	var/turf/target_turf = get_turf(src)
-	for(var/i = 1; i < t_range; i++)
+	for(var/i in 1 to t_range-1)
 		var/turf/new_turf = get_step(target_turf, direction)
 		target_turf = new_turf
 		if(new_turf.density)
@@ -26,11 +26,12 @@
 
 /obj/item/bodypart/chest/dismember()
 	var/mob/living/carbon/human/H = owner
-	if(!istype(H) || !H.dna.species:has_dismemberment) //human's species don't allow dismemberment
+	if(!istype(H) || !H.dna.species.has_dismemberment) //human's species don't allow dismemberment
 		return 0
 
 	var/organ_spilled = 0
 	var/turf/T = get_turf(H)
+	T.add_blood(H)
 	playsound(get_turf(owner), 'sound/misc/splort.ogg', 80, 1)
 	for(var/X in owner.internal_organs)
 		var/obj/item/organ/O = X
@@ -289,12 +290,12 @@
 
 //Regenerates all limbs. Returns amount of limbs regenerated
 /mob/living/proc/regenerate_limbs(noheal)
-	return
+	return 0
 
 /mob/living/carbon/human/regenerate_limbs(noheal)
 	var/list/limb_list = list("head", "chest", "r_arm", "l_arm", "r_leg", "l_leg")
 	for(var/Z in limb_list)
-		regenerate_limb(Z, noheal)
+		. += regenerate_limb(Z, noheal)
 
 /mob/living/proc/regenerate_limb(limb_zone, noheal)
 	return
@@ -302,7 +303,7 @@
 /mob/living/carbon/human/regenerate_limb(limb_zone, noheal)
 	var/obj/item/bodypart/L
 	if(get_bodypart(limb_zone))
-		return
+		return 0
 	L = newBodyPart(limb_zone, 0, 0, src)
 	if(L)
 		if(!noheal)

code/modules/surgery/bodyparts/head.dm

@@ -2,7 +2,7 @@
 
 /obj/item/bodypart/head
 	name = "head"
-	desc = "what a way to get a head in life..."
+	desc = "Didn't make sense not to live for fun, your brain gets smart but your head gets dumb."
 	icon_state = "head"
 	max_damage = 200
 	body_zone = "head"

code/modules/surgery/helpers.dm

@@ -23,11 +23,11 @@
 					if(!S.possible_locs.Find(selected_zone))
 						continue
 					if(affecting)
-						if(S.requires_missing_bodypart)
+						if(!S.requires_bodypart)
 							continue
 						if(S.requires_organic_bodypart && affecting.status == ORGAN_ROBOTIC)
 							continue
-					else if(H && !S.requires_missing_bodypart) //human with no limb in surgery zone when we need a limb
+					else if(H && S.requires_bodypart) //human with no limb in surgery zone when we need a limb
 						continue
 					if(!S.can_start(user, M))
 						continue
@@ -52,11 +52,11 @@
 						if(H)
 							affecting = H.get_bodypart(check_zone(selected_zone))
 						if(affecting)
-							if(procedure.requires_missing_bodypart)
+							if(!procedure.requires_bodypart)
 								return
 							if(procedure.requires_organic_bodypart && affecting.status == ORGAN_ROBOTIC)
 								return
-						else if(H && !procedure.requires_missing_bodypart)
+						else if(H && procedure.requires_bodypart)
 							return
 						if(!procedure.can_start(user, M))
 							return

code/modules/surgery/prosthetic_replacement.dm

@@ -3,7 +3,7 @@
 	steps = list(/datum/surgery_step/incise, /datum/surgery_step/clamp_bleeders, /datum/surgery_step/retract_skin, /datum/surgery_step/add_prosthetic)
 	species = list(/mob/living/carbon/human)
 	possible_locs = list("r_arm", "l_arm", "l_leg", "r_leg", "head")
-	requires_missing_bodypart = 1
+	requires_bodypart = FALSE //need a missing limb
 
 /datum/surgery/prosthetic_replacement/can_start(mob/user, mob/living/carbon/target)
 	if(!ishuman(target))

code/modules/surgery/surgery.dm

@@ -10,7 +10,7 @@
 	var/list/possible_locs = list() 							//Multiple locations -- c0
 	var/ignore_clothes = 0										//This surgery ignores clothes
 	var/obj/item/organ/organ									//Operable body part
-	var/requires_missing_bodypart = 0							//Surgery available only when a bodypart is present, or only when it is missing.
+	var/requires_bodypart = TRUE								//Surgery available only when a bodypart is present, or only when it is missing.
 
 /datum/surgery/proc/can_start(mob/user, mob/living/carbon/target)
 	// if 0 surgery wont show up in list