Giant spider nurses now have a chance of injecting their victims with spider eggs.

Spider nurses now have poison_per_bite chance (currently 10%) to inject a random non-robotic external limb with spider eggs.
These eggs will eventually hatch a number of spiderlings that will slowly grow inside their host, causing minor tox damage over time.
If the organ is removed from the host, the host dies, or the spiderling has matured sufficiently it will crawl out into freedom.

Medical scanners will register eggs and spiderlings as foreign bodies.

code/game/objects/effects/spiders.dm

@@ -78,18 +78,28 @@
 	New()
 		pixel_x = rand(3,-3)
 		pixel_y = rand(3,-3)
-		processing_objects.Add(src)
-		
+		processing_objects |= src
+
 /obj/effect/spider/eggcluster/Destroy()
-	processing_objects.Remove(src)
+	processing_objects -= src
+	if(istype(loc, /obj/item/organ/external))
+		var/obj/item/organ/external/O = loc
+		O.implants -= src
+
 	..()
 
 /obj/effect/spider/eggcluster/process()
 	amount_grown += rand(0,2)
 	if(amount_grown >= 100)
 		var/num = rand(6,24)
+		var/obj/item/organ/external/O = null
+		if(istype(loc, /obj/item/organ/external))
+			O = loc
+
 		for(var/i=0, i<num, i++)
 			var/obj/effect/spider/spiderling/spiderling = new(src.loc)
+			if(O)
+				O.implants += spiderling
 			spiderling.color = color
 			spiderling.set_light(light_range, light_power, light_color)
 		qdel(src)
@@ -101,6 +111,7 @@
 	anchored = 0
 	layer = 2.7
 	health = 3
+	var/last_itch = 0
 	var/amount_grown = -1
 	var/obj/machinery/atmospherics/unary/vent_pump/entry_vent
 	var/travelling_in_vent = 0
@@ -171,32 +182,47 @@
 			else
 				entry_vent = null
 	//=================
+	else if(isturf(loc))
+		if(prob(25))
+			var/list/nearby = trange(5, src) - loc
+			if(nearby.len)
+				var/target_atom = pick(nearby)
+				walk_to(src, target_atom, 5)
+				if(prob(25))
+					src.visible_message("<span class='notice'>\The [src] skitters[pick(" away"," around","")].</span>")
+		else if(prob(5))
+			//vent crawl!
+			for(var/obj/machinery/atmospherics/unary/vent_pump/v in view(7,src))
+				if(!v.welded)
+					entry_vent = v
+					walk_to(src, entry_vent, 5)
+					break
 
-	else if(prob(25))
-		var/list/nearby = oview(5, src)
-		if(nearby.len)
-			var/target_atom = pick(nearby)
-			walk_to(src, target_atom, 5)
-			if(prob(25))
-				src.visible_message("\blue \the [src] skitters[pick(" away"," around","")].")
-	else if(prob(5))
-		//vent crawl!
-		for(var/obj/machinery/atmospherics/unary/vent_pump/v in view(7,src))
-			if(!v.welded)
-				entry_vent = v
-				walk_to(src, entry_vent, 5)
-				break
-
-	if(prob(1))
-		src.visible_message("\blue \the [src] chitters.")
-	if(isturf(loc) && amount_grown > 0)
-		amount_grown += rand(0,2)
 		if(amount_grown >= 100)
 			var/spawn_type = pick(typesof(/mob/living/simple_animal/hostile/giant_spider))
 			var/mob/spiderspawn = new spawn_type(src.loc)
 			spiderspawn.color = color
 			spiderspawn.set_light(light_range, light_power, light_color)
 			qdel(src)
+	else if(isorgan(loc))
+		if(!amount_grown) amount_grown = 1
+		var/obj/item/organ/external/O = loc
+		if(!O.owner || O.owner.stat == DEAD || amount_grown > 80)
+			O.implants -= src
+			src.loc = O.owner ? O.owner.loc : O.loc
+			src.visible_message("<span class='warning'>\A [src] makes its way out of [O.owner ? "[O.owner]'s [O.name]" : "\the [O]"]!</span>")
+			if(O.owner)
+				O.owner.apply_damage(1, BRUTE, O.limb_name)
+		else if(prob(1))
+			O.owner.apply_damage(1, TOX, O.limb_name)
+			if(world.time > last_itch + 30 SECONDS)
+				last_itch = world.time
+				O.owner << "<span class='notice'>Your [O.name] itches...</span>"
+	else if(prob(1))
+		src.visible_message("<span class='notice'>\The [src] skitters.</span>")
+
+	if(amount_grown)
+		amount_grown += rand(0,2)
 
 /obj/effect/decal/cleanable/spiderling_remains
 	name = "spiderling remains"
@@ -214,7 +240,7 @@
 		icon_state = pick("cocoon1","cocoon2","cocoon3")
 
 /obj/effect/spider/cocoon/Destroy()
-	src.visible_message("\red \the [src] splits open.")
+	src.visible_message("<span class='warning'>\The [src] splits open.</span>")
 	for(var/atom/movable/A in contents)
 		A.loc = src.loc
 	return ..()

code/modules/mob/living/simple_animal/hostile/giant_spider.dm

@@ -64,15 +64,24 @@
 	move_to_delay = 4
 
 /mob/living/simple_animal/hostile/giant_spider/AttackingTarget()
-	..()
-	if(isliving(target_mob))
-		var/mob/living/L = target_mob
+	var/target = ..()
+	if(isliving(target))
+		var/mob/living/L = target
 		if(L.reagents)
 			L.reagents.add_reagent("toxin", poison_per_bite)
 			if(prob(poison_per_bite))
 				L << "\red You feel a tiny prick."
 				L.reagents.add_reagent(poison_type, 5)
 
+/mob/living/simple_animal/hostile/giant_spider/nurse/AttackingTarget()
+	var/target = ..()
+	if(ishuman(target))
+		var/mob/living/carbon/human/H = target
+		if(prob(poison_per_bite))
+			var/obj/item/organ/external/O = pick(H.organs)
+			if(!(O.status & ORGAN_ROBOT))
+				O.implants += new/obj/effect/spider/eggcluster(O)
+
 /mob/living/simple_animal/hostile/giant_spider/Life()
 	..()
 	if(!stat)