Adds Changeling Swap Forms Ability

- Chemical Cost: 40
- DNA Cost: 2
- Requires at least an aggressive grab, and 2 seconds to work
- Both subjects will slightly jitter during the brief process
- After two seconds if the changeling hasn't been interrupted, they swap minds

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

@@ -103,3 +103,61 @@
 			protected_dna |= new_dna
 			return
 	absorbed_dna |= new_dna
+
+
+
+
+/obj/effect/proc_holder/changeling/swap_form
+	name = "Swap Forms"
+	desc = "We force ourselves into the body of another form, pushing their consciousness into the form we left behind."
+	helptext = "We will bring all our abilities with us, but we will lose our old form DNA in exchange for the new one. The process will seem suspicious to any observers."
+	chemical_cost = 40
+	dna_cost = 2
+	req_human = 1 //Monkeys can't grab
+	genetic_damage = 50
+
+/obj/effect/proc_holder/changeling/swap_form/can_sting(var/mob/living/carbon/user)
+	if(!..())
+		return
+	var/obj/item/weapon/grab/G = user.get_active_hand()
+	if(!istype(G) || (G.state < GRAB_AGGRESSIVE))
+		user << "<span class='warning'>We must have an aggressive grab on creature in our active hand to do this!</span>"
+		return
+	var/mob/living/carbon/target = G.affecting
+	if((target.disabilities & NOCLONE) || (target.disabilities & HUSK))
+		user << "<span class='warning'>DNA of [target] is ruined beyond usability!</span>"
+		return
+	if(!check_dna_integrity(target) || !ishuman(target))
+		user << "<span class='warning'>[target] is not compatible with this ability.</span>"
+		return
+	return 1
+
+
+/obj/effect/proc_holder/changeling/swap_form/sting_action(var/mob/living/carbon/user)
+	var/obj/item/weapon/grab/G = user.get_active_hand()
+	var/mob/living/carbon/target = G.affecting
+	var/datum/changeling/changeling = user.mind.changeling
+
+	user << "<span class='notice'>We tighen our grip. We must hold still....</span>"
+	target.do_jitter_animation(500)
+	user.do_jitter_animation(500)
+
+	if(!do_mob(user,target,20))
+		user << "<span class='warning'The body swap has been interrupted!</span>"
+		return
+
+	target << "<span class='userdanger'>[user] tightens their grip as a painful sensation invades your body.</span>"
+
+	if(!changeling.has_dna(target.dna))
+		changeling.absorb_dna(target, user)
+	changeling.protected_dna -= user.dna
+	changeling.absorbed_dna -= user.dna
+
+	var/mob/dead/observer/ghost = target.ghostize(0)
+	user.mind.transfer_to(target)
+	if(ghost && ghost.mind)
+		ghost.mind.transfer_to(user)
+	user.key = ghost.key
+
+	user.Paralyse(2)
+	target << "<span class='warning'>Our genes cry out as we swap our [user] form for [target].</span>"

html/changelogs/ikarrus-changelingmindswap.yml

@@ -0,0 +1,6 @@
+author: Ikarrus
+
+delete-after: True
+
+changes: 
+  - rscadd: "Changelings now have the ability to swap forms with another being."