Frankenstein edition:

Limbs now store their own dna/species info. This allows transplanted limbs show up as they are, instead of conforming to mob. Vox-cat-monkey hybrids, rainbow skrells, go wild.
Also changed rejection to cause infection instead of straight up organ damage - wouldn't want your newly acquired catpaws fracture out of blue.
As a bonus, attacks are tracked per limb, so for example having kitty claws will give you the corresponding attack

code/modules/organs/organ.dm

@@ -23,6 +23,8 @@ var/list/organ_cache = list()
 	var/list/trace_chemicals = list() // traces of chemicals in the organ,
 									  // links chemical IDs to number of ticks for which they'll stay in the blood
 	germ_level = 0
+	var/datum/dna/dna
+	var/datum/species/species
 
 /obj/item/organ/proc/update_health()
 	return
@@ -34,6 +36,12 @@ var/list/organ_cache = list()
 		max_damage = min_broken_damage * 2
 	if(istype(holder))
 		src.owner = holder
+		species = all_species["Human"]
+		if(holder.dna)
+			dna = holder.dna.Clone()
+			species = all_species[dna.species]
+		else
+			log_debug("[src] at [loc] spawned without a proper DNA.")
 		var/mob/living/carbon/human/H = holder
 		if(istype(H))
 			if(internal)
@@ -42,10 +50,10 @@ var/list/organ_cache = list()
 					if(E.internal_organs == null)
 						E.internal_organs = list()
 					E.internal_organs |= src
-			if(H.dna)
+			if(dna)
 				if(!blood_DNA)
 					blood_DNA = list()
-				blood_DNA[H.dna.unique_enzymes] = H.dna.b_type
+				blood_DNA[dna.unique_enzymes] = dna.b_type
 		if(internal)
 			holder.internal_organs |= src
 
@@ -123,24 +131,23 @@ var/list/organ_cache = list()
 /obj/item/organ/proc/handle_rejection()
 	// Process unsuitable transplants. TODO: consider some kind of
 	// immunosuppressant that changes transplant data to make it match.
-	if(transplant_data)
-		if(!rejecting && prob(20) && owner.dna && blood_incompatible(transplant_data["blood_type"],owner.dna.b_type,owner.species,transplant_data["species"]))
-			rejecting = 1
+	if(dna)
+		if(!rejecting)
+			if(blood_incompatible(dna.b_type, owner.dna.b_type, species, owner.species))
+				rejecting = 1
 		else
 			rejecting++ //Rejection severity increases over time.
 			if(rejecting % 10 == 0) //Only fire every ten rejection ticks.
 				switch(rejecting)
 					if(1 to 50)
-						take_damage(1)
+						germ_level++
 					if(51 to 200)
-						owner.reagents.add_reagent("toxin", 1)
-						take_damage(1)
+						germ_level += rand(1,2)
 					if(201 to 500)
-						take_damage(rand(2,3))
-						owner.reagents.add_reagent("toxin", 2)
+						germ_level += rand(2,3)
 					if(501 to INFINITY)
-						take_damage(4)
-						owner.reagents.add_reagent("toxin", rand(3,5))
+						germ_level += rand(3,5)
+						owner.reagents.add_reagent("toxin", rand(1,2))
 
 /obj/item/organ/proc/receive_chem(chemical as obj)
 	return 0

code/modules/organs/organ_icon.dm

@@ -17,11 +17,23 @@ var/global/list/limb_icon_cache = list()
 	s_col = null
 	if(status & ORGAN_ROBOT)
 		return
+	if(species && human.species && species.name != human.species.name)
+		return
 	if(!isnull(human.s_tone) && (human.species.flags & HAS_SKIN_TONE))
 		s_tone = human.s_tone
 	if(human.species.flags & HAS_SKIN_COLOR)
 		s_col = list(human.r_skin, human.g_skin, human.b_skin)
 
+/obj/item/organ/external/proc/sync_colour_to_dna()
+	s_tone = null
+	s_col = null
+	if(status & ORGAN_ROBOT)
+		return
+	if(!isnull(dna.GetUIValue(DNA_UI_SKIN_TONE)) && (species.flags & HAS_SKIN_TONE))
+		s_tone = dna.GetUIValue(DNA_UI_SKIN_TONE)
+	if(species.flags & HAS_SKIN_COLOR)
+		s_col = list(dna.GetUIValue(DNA_UI_SKIN_R), dna.GetUIValue(DNA_UI_SKIN_G), dna.GetUIValue(DNA_UI_SKIN_B))
+
 /obj/item/organ/external/head/sync_colour_to_human(var/mob/living/carbon/human/human)
 	..()
 	var/obj/item/organ/eyes/eyes = owner.internal_organs_by_name["eyes"]
@@ -35,10 +47,10 @@ var/global/list/limb_icon_cache = list()
 
 	..()
 	overlays.Cut()
-	if(owner.species.has_organ["eyes"])
+	if(species.has_organ["eyes"])
 		var/obj/item/organ/eyes/eyes = owner.internal_organs_by_name["eyes"]
-		if(owner.species.eyes)
-			var/icon/eyes_icon = new/icon('icons/mob/human_face.dmi', owner.species.eyes)
+		if(species.eyes)
+			var/icon/eyes_icon = new/icon('icons/mob/human_face.dmi', species.eyes)
 			if(eyes)
 				eyes_icon.Blend(rgb(eyes.eye_colour[1], eyes.eye_colour[2], eyes.eye_colour[3]), ICON_ADD)
 			else
@@ -46,14 +58,14 @@ var/global/list/limb_icon_cache = list()
 			mob_icon.Blend(eyes_icon, ICON_OVERLAY)
 			overlays |= eyes_icon
 
-	if(owner.lip_style && (owner.species && (owner.species.flags & HAS_LIPS)))
+	if(owner.lip_style && (species && (species.flags & HAS_LIPS)))
 		var/icon/lip_icon = new/icon('icons/mob/human_face.dmi', "lips_[owner.lip_style]_s")
 		overlays |= lip_icon
 		mob_icon.Blend(lip_icon, ICON_OVERLAY)
 
 	if(owner.f_style)
 		var/datum/sprite_accessory/facial_hair_style = facial_hair_styles_list[owner.f_style]
-		if(facial_hair_style && facial_hair_style.species_allowed && (owner.species.name in facial_hair_style.species_allowed))
+		if(facial_hair_style && facial_hair_style.species_allowed && (species.name in facial_hair_style.species_allowed))
 			var/icon/facial_s = new/icon("icon" = facial_hair_style.icon, "icon_state" = "[facial_hair_style.icon_state]_s")
 			if(facial_hair_style.do_colouration)
 				facial_s.Blend(rgb(owner.r_facial, owner.g_facial, owner.b_facial), ICON_ADD)
@@ -61,7 +73,7 @@ var/global/list/limb_icon_cache = list()
 
 	if(owner.h_style && !(owner.head && (owner.head.flags & BLOCKHEADHAIR)))
 		var/datum/sprite_accessory/hair_style = hair_styles_list[owner.h_style]
-		if(hair_style && (owner.species.name in hair_style.species_allowed))
+		if(hair_style && (species.name in hair_style.species_allowed))
 			var/icon/hair_s = new/icon("icon" = hair_style.icon, "icon_state" = "[hair_style.icon_state]_s")
 			if(hair_style.do_colouration)
 				hair_s.Blend(rgb(owner.r_hair, owner.g_hair, owner.b_hair), ICON_ADD)
@@ -75,25 +87,25 @@ var/global/list/limb_icon_cache = list()
 	if(force_icon)
 		mob_icon = new /icon(force_icon, "[icon_name]")
 	else
-		if(!owner)
+		if(!dna)
 			mob_icon = new /icon('icons/mob/human_races/r_human.dmi', "[icon_name][gendered_icon ? "_f" : ""]")
 		else
 
 			if(gendered_icon)
-				if(owner.gender == FEMALE)
+				if(dna.GetUIState(DNA_UI_GENDER))
 					gender = "f"
 				else
 					gender = "m"
 
 			if(skeletal)
 				mob_icon = new /icon('icons/mob/human_races/r_skeleton.dmi', "[icon_name][gender ? "_[gender]" : ""]")
-			else if ((status & ORGAN_ROBOT) && !(owner.species && owner.species.flags & IS_SYNTHETIC))
+			else if ((status & ORGAN_ROBOT) && !(species && species.flags & IS_SYNTHETIC))
 				mob_icon = new /icon('icons/mob/human_races/robotic.dmi', "[icon_name][gender ? "_[gender]" : ""]")
 			else
 				if (status & ORGAN_MUTATED)
-					mob_icon = new /icon(owner.species.deform, "[icon_name][gender ? "_[gender]" : ""]")
+					mob_icon = new /icon(species.deform, "[icon_name][gender ? "_[gender]" : ""]")
 				else
-					mob_icon = new /icon(owner.species.icobase, "[icon_name][gender ? "_[gender]" : ""]")
+					mob_icon = new /icon(species.icobase, "[icon_name][gender ? "_[gender]" : ""]")
 
 				if(status & ORGAN_DEAD)
 					mob_icon.ColorTone(rgb(10,50,0))

code/modules/organs/robolimbs.dm

@@ -7,6 +7,7 @@ var/global/datum/robolimb/basic_robolimb
 	for(var/limb_type in typesof(/datum/robolimb))
 		var/datum/robolimb/R = new limb_type()
 		all_robolimbs[R.company] = R
+		world << "Adding [R.company] as [R], [R.type]"
 		if(!R.unavailable_at_chargen)
 			chargen_robolimbs[R.company] = R