Fixes a fuck ton more harddels (#58779)

Redoes how geese handle eating shit, it was fucking stupid and caused harddels, and while this method is technically slower in the best case, it's a fucking goose
Fixes action related harddels, I hate how they work but at least this way they won't hold refs.
Fixes the hierophont causing its beacon to harddel
Removes the M variable from megafauna actions, it was used like a typed owner and caused harddels, so I burned it
Fixes target and targets_from harddels, replaces all setters of target with LoseTarget and GiveTarget, which should help maintain behavior. I'm not sure if this breaks anything, but if it does we should fix the assumptions that code makes instead of reverting this change
Fixes more area_senstive_contents related harddels, we need to allow the mob to move before clearing out its list.
Fixes marked object harddels (I'm coming for you admin team)
Fixes a language based human harddel
Fixes managed overlay related harddels (This was just emissive blockers, but I think this is a good safety net to have. If we clear the overlay list we should clear this one as well)
Fixes bot core harddels, I hate the fact that this exists but it has no reason to know who its owner is
Adds a walk(src, 0) to simple_animal destroy, it's the best bang for the buck in terms of stopping spurious harddels. Walk related harddels aren't that expensive in the first place, since byond does the same thing I'm doing here, but this makes finding mob harddels easier, so let's go with it
I fixed another source of part harddels, I hate fullupgrade so much
Fixes all the sound loop harddels

code/_onclick/other_mobs.dm

@@ -230,7 +230,7 @@
 /mob/living/simple_animal/hostile/UnarmedAttack(atom/attack_target, proximity_flag, list/modifiers)
 	if(LIVING_UNARMED_ATTACK_BLOCKED(attack_target))
 		return
-	target = attack_target
+	GiveTarget(attack_target)
 	if(dextrous && (isitem(attack_target) || !combat_mode))
 		..()
 	else

code/controllers/subsystem/atoms.dm

@@ -64,6 +64,9 @@ SUBSYSTEM_DEF(atoms)
 	if(late_loaders.len)
 		for(var/I in 1 to late_loaders.len)
 			var/atom/A = late_loaders[I]
+			//I hate that we need this
+			if(QDELETED(A))
+				continue
 			A.LateInitialize()
 		testing("Late initialized [late_loaders.len] atoms")
 		late_loaders.Cut()

code/datums/action.dm

@@ -47,6 +47,7 @@
 				return
 			Remove(owner)
 		owner = M
+		RegisterSignal(owner, COMSIG_PARENT_QDELETING, .proc/owner_deleted)
 
 		//button id generation
 		var/counter = 0
@@ -72,13 +73,19 @@
 	else
 		Remove(owner)
 
+/datum/action/proc/owner_deleted(datum/source)
+	SIGNAL_HANDLER
+	Remove(owner)
+
 /datum/action/proc/Remove(mob/M)
 	if(M)
 		if(M.client)
 			M.client.screen -= button
 		LAZYREMOVE(M.actions, src)
 		M.update_action_buttons()
-	owner = null
+	if(owner)
+		UnregisterSignal(owner, COMSIG_PARENT_QDELETING)
+		owner = null
 	button.moved = FALSE //so the button appears in its normal position when given to another owner.
 	button.locked = FALSE
 	button.id = null

code/datums/components/acid.dm

@@ -55,8 +55,7 @@
 
 /datum/component/acid/Destroy(force, silent)
 	STOP_PROCESSING(SSacid, src)
-	if(sizzle)
-		QDEL_NULL(sizzle)
+	QDEL_NULL(sizzle)
 	if(process_effect)
 		QDEL_NULL(process_effect)
 	UnregisterSignal(parent, COMSIG_ATOM_UPDATE_OVERLAYS)

code/datums/components/plumbing/_plumbing.dm

@@ -245,7 +245,6 @@
 /// Toggle our machinery on or off. This is called by a hook from default_unfasten_wrench with anchored as only param, so we dont have to copypaste this on every object that can move
 /datum/component/plumbing/proc/toggle_active(obj/O, new_state)
 	SIGNAL_HANDLER
-
 	if(new_state)
 		enable()
 	else
@@ -314,12 +313,18 @@
 
 /datum/component/plumbing/proc/set_recipient_reagents_holder(datum/reagents/receiver)
 	if(recipient_reagents_holder)
-		UnregisterSignal(recipient_reagents_holder, list(COMSIG_PARENT_QDELETING)) //stop tracking whoever we were tracking
+		UnregisterSignal(recipient_reagents_holder, COMSIG_PARENT_QDELETING) //stop tracking whoever we were tracking
 	if(receiver)
-		RegisterSignal(receiver, list(COMSIG_PARENT_QDELETING), .proc/set_recipient_reagents_holder) //so on deletion it calls this proc again, but with no value to set
+		RegisterSignal(receiver, COMSIG_PARENT_QDELETING, .proc/handle_reagent_del) //on deletion call a wrapper proc that clears us, and maybe reagents too
 
 	recipient_reagents_holder = receiver
 
+/datum/component/plumbing/proc/handle_reagent_del(datum/source)
+	SIGNAL_HANDLER
+	if(source == reagents)
+		reagents = null
+	if(source == recipient_reagents_holder)
+		set_recipient_reagents_holder(null)
 
 ///has one pipe input that only takes, example is manual output pipe
 /datum/component/plumbing/simple_demand

code/game/atoms.dm

@@ -284,11 +284,12 @@
 			AA.remove_from_hud(src)
 
 	if(reagents)
-		qdel(reagents)
+		QDEL_NULL(reagents)
 
 	orbiters = null // The component is attached to us normaly and will be deleted elsewhere
 
 	LAZYCLEARLIST(overlays)
+	LAZYCLEARLIST(managed_overlays)
 
 	QDEL_NULL(light)
 	QDEL_NULL(ai_controller)

code/game/atoms_movable.dm

@@ -123,9 +123,6 @@
 
 	. = ..()
 
-	//We add ourselves to this list, best to clear it out
-	LAZYCLEARLIST(area_sensitive_contents)
-
 	for(var/movable_content in contents)
 		qdel(movable_content)
 
@@ -133,6 +130,10 @@
 
 	moveToNullspace()
 
+	//We add ourselves to this list, best to clear it out
+	//DO it after moveToNullspace so memes can be had
+	LAZYCLEARLIST(area_sensitive_contents)
+
 	vis_contents.Cut()
 
 /atom/movable/proc/update_emissive_block()

code/game/machinery/Sleeper.dm

@@ -269,21 +269,8 @@
 	base_icon_state = "sleeper_s"
 	controls_inside = TRUE
 
-/obj/machinery/sleeper/syndie/fullupgrade/Initialize()
-	. = ..()
-
-	// Cache the old_parts first, we'll delete it after we've changed component_parts to a new list.
-	// This stops handle_atom_del being called on every part when not necessary.
-	var/list/old_parts = component_parts.Copy()
-
-	component_parts = list()
-	component_parts += new /obj/item/stock_parts/matter_bin/bluespace(src)
-	component_parts += new /obj/item/stock_parts/manipulator/femto(src)
-	component_parts += new /obj/item/stack/sheet/glass(src, 2)
-	component_parts += new /obj/item/stack/cable_coil(src, 1)
-
-	QDEL_LIST(old_parts)
-	RefreshParts()
+/obj/machinery/sleeper/syndie/fullupgrade
+	circuit = /obj/item/circuitboard/machine/sleeper/fullupgrade
 
 /obj/machinery/sleeper/old
 	icon_state = "oldpod"

code/game/machinery/computer/arcade/orion_event.dm

@@ -526,7 +526,7 @@
 				playsound(game, 'sound/items/weeoo1.ogg', 100, FALSE)
 				for(var/i, i<=3, i++)
 					var/mob/living/simple_animal/hostile/syndicate/ranged/smg/orion/spaceport_security = new(get_turf(src))
-					spaceport_security.target = usr
+					spaceport_security.GiveTarget(usr)
 	game.fuel += fuel
 	game.food += food
 

code/game/machinery/fat_sucker.dm

@@ -32,6 +32,10 @@
 	soundloop = new(list(src),  FALSE)
 	update_appearance()
 
+/obj/machinery/fat_sucker/Destroy()
+	QDEL_NULL(soundloop)
+	. = ..()
+
 /obj/machinery/fat_sucker/RefreshParts()
 	..()
 	var/rating = 0

code/game/machinery/roulette_machine.dm

@@ -54,6 +54,10 @@
 	jackpot_loop = new(list(src), FALSE)
 	wires = new /datum/wires/roulette(src)
 
+/obj/machinery/roulette/Destroy()
+	QDEL_NULL(jackpot_loop)
+	. = ..()
+
 /obj/machinery/roulette/obj_break(damage_flag)
 	prize_theft(0.05)
 	. = ..()

code/game/objects/items/circuitboards/machine_circuitboards.dm

@@ -776,6 +776,16 @@
 		/obj/item/stack/cable_coil = 1,
 		/obj/item/stack/sheet/glass = 2)
 
+/obj/item/circuitboard/machine/sleeper/fullupgrade
+	name = "Sleeper (Machine Board)"
+	icon_state = "medical"
+	build_path = /obj/machinery/sleeper/syndie/fullupgrade
+	req_components = list(
+		/obj/item/stock_parts/matter_bin/bluespace = 1,
+		/obj/item/stock_parts/manipulator/femto = 1,
+		/obj/item/stack/cable_coil = 1,
+		/obj/item/stack/sheet/glass = 2)
+
 /obj/item/circuitboard/machine/sleeper/party
 	name = "Party Pod (Machine Board)"
 	build_path = /obj/machinery/sleeper/party

code/modules/admin/view_variables/mark_datum.dm

@@ -2,11 +2,18 @@
 	if(!holder)
 		return
 	if(holder.marked_datum)
+		holder.UnregisterSignal(holder.marked_datum, COMSIG_PARENT_QDELETING)
 		vv_update_display(holder.marked_datum, "marked", "")
 	holder.marked_datum = D
+	holder.RegisterSignal(holder.marked_datum, COMSIG_PARENT_QDELETING, /datum/admins/proc/handle_marked_del)
 	vv_update_display(D, "marked", VV_MSG_MARKED)
 
 /client/proc/mark_datum_mapview(datum/D as mob|obj|turf|area in view(view))
 	set category = "Debug"
 	set name = "Mark Object"
 	mark_datum(D)
+
+/datum/admins/proc/handle_marked_del(datum/source)
+	SIGNAL_HANDLER
+	UnregisterSignal(marked_datum, COMSIG_PARENT_QDELETING)
+	marked_datum = null

code/modules/cargo/supplypod.dm

@@ -459,12 +459,18 @@
 	glow_effect.icon_state = "pod_glow_" + GLOB.podstyles[style][POD_GLOW]
 	vis_contents += glow_effect
 	glow_effect.layer = GASFIRE_LAYER
+	RegisterSignal(glow_effect, COMSIG_PARENT_QDELETING, .proc/remove_glow)
 
 /obj/structure/closet/supplypod/proc/endGlow()
 	if(!glow_effect)
 		return
 	glow_effect.layer = LOW_ITEM_LAYER
 	glow_effect.fadeAway(delays[POD_OPENING])
+	remove_glow()
+
+/obj/structure/closet/supplypod/proc/remove_glow()
+	SIGNAL_HANDLER
+	UnregisterSignal(glow_effect, COMSIG_PARENT_QDELETING)
 	glow_effect = null
 
 /obj/structure/closet/supplypod/Destroy()

code/modules/clothing/head/misc.dm

@@ -52,7 +52,7 @@
 		var/wait_how_many_bees_did_that_guy_pull_out_of_his_hat = rand(4, 8)
 		for(var/b in 1 to wait_how_many_bees_did_that_guy_pull_out_of_his_hat)
 			var/mob/living/simple_animal/hostile/poison/bees/barry = new(get_turf(magician))
-			barry.target = magician
+			barry.GiveTarget(magician)
 			if(prob(20))
 				barry.say(pick("BUZZ BUZZ", "PULLING A RABBIT OUT OF A HAT IS A TIRED TROPE", "I DIDN'T ASK TO BEE HERE"), forced = "bee hat")
 	else

code/modules/clothing/spacesuits/hardsuit.dm

@@ -33,6 +33,7 @@
 
 /obj/item/clothing/head/helmet/space/hardsuit/Destroy()
 	. = ..()
+	QDEL_NULL(soundloop)
 	STOP_PROCESSING(SSobj, src)
 
 /obj/item/clothing/head/helmet/space/hardsuit/attack_self(mob/user)

code/modules/food_and_drinks/kitchen_machinery/griddle.dm

@@ -29,6 +29,10 @@
 		variant = rand(1,3)
 	RegisterSignal(src, COMSIG_ATOM_EXPOSE_REAGENT, .proc/on_expose_reagent)
 
+/obj/machinery/griddle/Destroy()
+	QDEL_NULL(grill_loop)
+	. = ..()
+
 /obj/machinery/griddle/crowbar_act(mob/living/user, obj/item/I)
 	. = ..()
 	if(flags_1 & NODECONSTRUCT_1)

code/modules/hydroponics/beekeeping/beebox.dm

@@ -206,7 +206,7 @@
 				continue
 			if(B.loc == src)
 				B.forceMove(drop_location())
-			B.target = user
+			B.GiveTarget(user)
 			bees = TRUE
 		if(bees)
 			visible_message("<span class='danger'>[user] disturbs the bees!</span>")

code/modules/language/language_holder.dm

@@ -50,7 +50,7 @@ Key procs
 	/// Currently spoken language
 	var/selected_language
 	/// Tracks the entity that owns the holder.
-	var/owner
+	var/atom/owner
 
 /// Initializes, and copies in the languages from the current atom if available.
 /datum/language_holder/New(_owner)
@@ -63,6 +63,7 @@ Key procs
 
 /datum/language_holder/Destroy()
 	QDEL_NULL(language_menu)
+	owner = null
 	return ..()
 
 /// Grants the supplied language.

code/modules/mob/living/simple_animal/bot/bot.dm

@@ -897,12 +897,10 @@ Pass a positive integer as an argument to override a bot's default speed.
 /obj/machinery/bot_core
 	use_power = NO_POWER_USE
 	anchored = FALSE
-	var/mob/living/simple_animal/bot/owner = null
 
 /obj/machinery/bot_core/Initialize()
 	. = ..()
-	owner = loc
-	if(!istype(owner))
+	if(!isbot(loc))
 		return INITIALIZE_HINT_QDEL
 
 /mob/living/simple_animal/bot/proc/topic_denied(mob/user) //Access check proc for bot topics! Remember to place in a bot's individual Topic if desired.

code/modules/mob/living/simple_animal/eldritch_demons.dm

@@ -250,7 +250,7 @@
 			return
 
 /mob/living/simple_animal/hostile/eldritch/armsy/Shoot(atom/targeted_atom)
-	target = targeted_atom
+	GiveTarget(targeted_atom)
 	AttackingTarget()
 
 /mob/living/simple_animal/hostile/eldritch/armsy/AttackingTarget()
@@ -261,7 +261,7 @@
 	if(target == back || target == front)
 		return
 	if(back)
-		back.target = target
+		back.GiveTarget(target)
 		back.AttackingTarget()
 	if(!Adjacent(target))
 		return

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

@@ -166,7 +166,7 @@
 			var/obj/structure/beebox/BB = target
 			forceMove(BB)
 			toggle_ai(AI_IDLE)
-			target = null
+			LoseTarget()
 			wanted_objects -= beehometypecache //so we don't attack beeboxes when not going home
 		return //no don't attack the goddamm box
 	else
@@ -193,10 +193,10 @@
 
 /mob/living/simple_animal/hostile/poison/bees/proc/pollinate(obj/machinery/hydroponics/Hydro)
 	if(!istype(Hydro) || !Hydro.myseed || Hydro.dead || Hydro.recent_bee_visit)
-		target = null
+		LoseTarget()
 		return
 
-	target = null //so we pick a new hydro tray next FindTarget(), instead of loving the same plant for eternity
+	LoseTarget() //so we pick a new hydro tray next FindTarget(), instead of loving the same plant for eternity
 	wanted_objects -= hydroponicstypecache //so we only hunt them while they're alive/seeded/not visisted
 	Hydro.recent_bee_visit = TRUE
 	addtimer(VARSET_CALLBACK(Hydro, recent_bee_visit, FALSE), BEE_TRAY_RECENT_VISIT)
@@ -232,7 +232,7 @@
 			if(idle <= BEE_IDLE_GOHOME && prob(BEE_PROB_GOHOME))
 				if(!FindTarget())
 					wanted_objects |= beehometypecache //so we don't attack beeboxes when not going home
-					target = beehome
+					GiveTarget(beehome)
 	if(!beehome) //add outselves to a beebox (of the same reagent) if we have no home
 		for(var/obj/structure/beebox/BB in view(vision_range, src))
 			if(reagent_incompatible(BB.queen_bee) || BB.bees.len >= BB.get_max_bees())

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

@@ -36,7 +36,6 @@
 	var/icon_vomit = "vomit"
 	var/icon_vomit_end = "vomit_end"
 	var/message_cooldown = 0
-	var/list/nummies = list()
 	var/choking = FALSE
 
 /mob/living/simple_animal/hostile/retaliate/goose/Initialize()
@@ -46,27 +45,21 @@
 /mob/living/simple_animal/hostile/retaliate/goose/proc/goosement(atom/movable/AM, OldLoc, Dir, Forced)
 	if(stat == DEAD)
 		return
-	nummies.Cut()
-	nummies += loc.contents
 	if(prob(5) && random_retaliate)
 		Retaliate()
 
 /mob/living/simple_animal/hostile/retaliate/goose/handle_automated_action()
-	if(length(nummies))
-		var/obj/item/E = locate() in nummies
-		if(E && E.loc == loc)
-			feed(E)
-		nummies -= E
+	var/obj/item/eat_it_motherfucker = pick(locate(/obj/item) in loc)
+	if(!eat_it_motherfucker)
+		return
+	feed(eat_it_motherfucker)
 
 /mob/living/simple_animal/hostile/retaliate/goose/vomit/handle_automated_action()
-	if(length(nummies))
-		var/obj/item/E = pick(nummies)
-		if(!E.has_material_type(/datum/material/plastic))
-			nummies -= E // remove non-plastic item from queue
-			E = locate(/obj/item/reagent_containers/food) in nummies // find food
-		if(E && E.loc == loc)
-			feed(E)
-		nummies -= E
+	for(var/obj/item/eat_it_motherfucker in loc)
+		if(!eat_it_motherfucker.has_material_type(/datum/material/plastic))
+			continue
+		feed(eat_it_motherfucker)
+		break
 
 /mob/living/simple_animal/hostile/retaliate/goose/proc/feed(obj/item/suffocator)
 	if(stat == DEAD || choking) // plapatin I swear to god
@@ -174,7 +167,7 @@
 	if (stat == DEAD)
 		return
 	var/turf/T = get_turf(src)
-	var/obj/item/reagent_containers/food/consumed = locate() in contents //Barf out a single food item from our guts
+	var/obj/item/consumed = locate() in contents //Barf out a single food item from our guts
 	choking = FALSE // assume birdboat is vomiting out whatever he was choking on
 	if (prob(50) && consumed)
 		barf_food(consumed)

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

@@ -3,6 +3,7 @@
 	stop_automated_movement_when_pulled = 0
 	obj_damage = 40
 	environment_smash = ENVIRONMENT_SMASH_STRUCTURES //Bitflags. Set to ENVIRONMENT_SMASH_STRUCTURES to break closets,tables,racks, etc; ENVIRONMENT_SMASH_WALLS for walls; ENVIRONMENT_SMASH_RWALLS for rwalls
+	///The current target of our attacks, use GiveTarget and LoseTarget to set this var
 	var/atom/target
 	var/ranged = FALSE
 	var/rapid = 0 //How many shots per volley.
@@ -46,6 +47,7 @@
 	var/stat_attack = CONSCIOUS
 	var/stat_exclusive = FALSE //Mobs with this set to TRUE will exclusively attack things defined by stat_attack, stat_attack DEAD means they will only attack corpses
 	var/attack_same = 0 //Set us to 1 to allow us to attack our own faction
+	//Use set_targets_from to modify this var
 	var/atom/targets_from = null //all range/attack/etc. calculations should be done from this atom, defaults to the mob itself, useful for Vehicles and such
 	var/attack_all_objects = FALSE //if true, equivalent to having a wanted_objects list containing ALL objects.
 	var/lose_patience_timer_id //id for a timer to call LoseTarget(), used to stop mobs fixating on a target they can't reach
@@ -68,12 +70,14 @@
 	. = ..()
 
 	if(!targets_from)
-		targets_from = src
+		set_targets_from(src)
 	wanted_objects = typecacheof(wanted_objects)
 
 
 /mob/living/simple_animal/hostile/Destroy()
-	targets_from = null
+	set_targets_from(null)
+	//We can't use losetarget here because fucking cursed blobs override it to do nothing the motherfuckers
+	GiveTarget(null)
 	return ..()
 
 /mob/living/simple_animal/hostile/Life(delta_time = SSMOBS_DT, times_fired)
@@ -253,12 +257,12 @@
 	return FALSE
 
 /mob/living/simple_animal/hostile/proc/GiveTarget(new_target)//Step 4, give us our selected target
-	target = new_target
+	add_target(new_target)
 	LosePatience()
 	if(target != null)
 		GainPatience()
 		Aggro()
-		return 1
+		return TRUE
 
 //What we do after closing in
 /mob/living/simple_animal/hostile/proc/MeleeAction(patience = TRUE)
@@ -337,7 +341,7 @@
 	. = ..()
 	if(!ckey && !stat && search_objects < 3 && . > 0)//Not unconscious, and we don't ignore mobs
 		if(search_objects)//Turn off item searching and ignore whatever item we were looking at, we're more concerned with fight or flight
-			target = null
+			LoseTarget()
 			LoseSearchObjects()
 		if(AIStatus != AI_ON && AIStatus != AI_OFF)
 			toggle_ai(AI_ON)
@@ -364,7 +368,7 @@
 	taunt_chance = initial(taunt_chance)
 
 /mob/living/simple_animal/hostile/proc/LoseTarget()
-	target = null
+	GiveTarget(null)
 	approaching_target = FALSE
 	in_melee = FALSE
 	walk(src, 0)
@@ -511,7 +515,7 @@
 
 /mob/living/simple_animal/hostile/RangedAttack(atom/A, modifiers) //Player firing
 	if(ranged && ranged_cooldown <= world.time)
-		target = A
+		GiveTarget(A)
 		OpenFire(A)
 	return ..()
 
@@ -652,3 +656,28 @@
 		if(charge_state)
 			charge_state = FALSE
 			update_icons()
+
+/mob/living/simple_animal/hostile/proc/set_targets_from(atom/target_from)
+	if(targets_from)
+		UnregisterSignal(targets_from, COMSIG_PARENT_QDELETING)
+	targets_from = target_from
+	if(targets_from)
+		RegisterSignal(targets_from, COMSIG_PARENT_QDELETING, .proc/handle_targets_from_del)
+
+/mob/living/simple_animal/hostile/proc/handle_targets_from_del(datum/source)
+	SIGNAL_HANDLER
+	if(targets_from != src)
+		set_targets_from(src)
+
+/mob/living/simple_animal/hostile/proc/handle_target_del(datum/source)
+	SIGNAL_HANDLER
+	UnregisterSignal(target, COMSIG_PARENT_QDELETING)
+	target = null
+	LoseTarget()
+
+/mob/living/simple_animal/hostile/proc/add_target(new_target)
+	if(target)
+		UnregisterSignal(target, COMSIG_PARENT_QDELETING)
+	target = new_target
+	if(target)
+		RegisterSignal(target, COMSIG_PARENT_QDELETING, .proc/handle_target_del)

code/modules/mob/living/simple_animal/hostile/jungle/leaper.dm

@@ -139,7 +139,7 @@
 
 /mob/living/simple_animal/hostile/jungle/leaper/CtrlClickOn(atom/A)
 	face_atom(A)
-	target = A
+	GiveTarget(A)
 	if(!isturf(loc))
 		return
 	if(next_move > world.time)

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

@@ -69,9 +69,9 @@
 /mob/living/simple_animal/hostile/syndicate/mecha_pilot/proc/enter_mecha(obj/vehicle/sealed/mecha/M)
 	if(!M)
 		return 0
-	target = null //Target was our mecha, so null it out
+	LoseTarget() //Target was our mecha, so null it out
 	M.aimob_enter_mech(src)
-	targets_from = M
+	set_targets_from(M)
 	allow_movement_on_non_turfs = TRUE //duh
 	var/do_ranged = 0
 	for(var/equip in mecha.equipment)
@@ -97,14 +97,14 @@
 
 	mecha.aimob_exit_mech(src)
 	allow_movement_on_non_turfs = FALSE
-	targets_from = src
+	set_targets_from(src)
 
 	//Find a new mecha
 	wanted_objects = typecacheof(/obj/vehicle/sealed/mecha/combat, TRUE)
 	var/search_aggressiveness = 2
 	for(var/obj/vehicle/sealed/mecha/combat/C in range(vision_range,src))
 		if(is_valid_mecha(C))
-			target = C
+			GiveTarget(C)
 			search_aggressiveness = 3 //We can see a mech? RUN FOR IT, IGNORE MOBS!
 			break
 	search_objects = search_aggressiveness
@@ -188,7 +188,7 @@
 				return
 			else
 				if(!CanAttack(M))
-					target = null
+					LoseTarget()
 					return
 
 		return target.attack_animal(src)
@@ -201,7 +201,7 @@
 	if(!mecha)
 		for(var/obj/vehicle/sealed/mecha/combat/mecha_in_range in range(src,vision_range))
 			if(is_valid_mecha(mecha_in_range))
-				target = mecha_in_range //Let's nab it!
+				GiveTarget(mecha_in_range) //Let's nab it!
 				minimum_distance = 1
 				ranged = 0
 				break

code/modules/mob/living/simple_animal/hostile/megafauna/drake.dm

@@ -311,7 +311,7 @@
 	if(stat || swooping)
 		return
 	if(manual_target)
-		target = manual_target
+		GiveTarget(manual_target)
 	if(!target)
 		return
 	stop_automated_movement = TRUE

code/modules/mob/living/simple_animal/hostile/megafauna/hierophant.dm

@@ -90,6 +90,10 @@ Difficulty: Hard
 	. = ..()
 	spawned_beacon = new(loc)
 
+/mob/living/simple_animal/hostile/megafauna/hierophant/Destroy()
+	QDEL_NULL(spawned_beacon)
+	. = ..()
+
 /datum/action/innate/megafauna_attack/blink
 	name = "Blink To Target"
 	icon_icon = 'icons/mob/actions/actions_items.dmi'
@@ -412,10 +416,6 @@ Difficulty: Hard
 		set_stat(CONSCIOUS) // deathgasp won't run if dead, stupid
 		..(force_grant = stored_nearby)
 
-/mob/living/simple_animal/hostile/megafauna/hierophant/Destroy()
-	qdel(spawned_beacon)
-	. = ..()
-
 /mob/living/simple_animal/hostile/megafauna/hierophant/devour(mob/living/L)
 	for(var/obj/item/W in L)
 		if(!L.dropItemToGround(W))

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

@@ -75,7 +75,7 @@
 		for(var/i = 1 to nest_range)
 			closest = get_step(closest, get_dir(closest, src))
 		forceMove(closest) // someone teleported out probably and the megafauna kept chasing them
-		target = null
+		LoseTarget()
 		return
 	return ..()
 
@@ -179,16 +179,15 @@
 	name = "Megafauna Attack"
 	icon_icon = 'icons/mob/actions/actions_animal.dmi'
 	button_icon_state = ""
-	var/mob/living/simple_animal/hostile/megafauna/M
 	var/chosen_message
 	var/chosen_attack_num = 0
 
 /datum/action/innate/megafauna_attack/Grant(mob/living/L)
-	if(istype(L, /mob/living/simple_animal/hostile/megafauna))
-		M = L
-		return ..()
-	return FALSE
+	if(!ismegafauna(L))
+		return FALSE
+	return ..()
 
 /datum/action/innate/megafauna_attack/Activate()
-	M.chosen_attack = chosen_attack_num
-	to_chat(M, chosen_message)
+	var/mob/living/simple_animal/hostile/megafauna/fauna = owner
+	fauna.chosen_attack = chosen_attack_num
+	to_chat(fauna, chosen_message)

code/modules/mob/living/simple_animal/hostile/mining_mobs/goldgrub.dm

@@ -93,7 +93,7 @@
 		G.is_burrowed = TRUE
 
 /mob/living/simple_animal/hostile/asteroid/goldgrub/GiveTarget(new_target)
-	target = new_target
+	add_target(new_target)
 	if(target != null)
 		if(istype(target, /obj/item/stack/ore))
 			visible_message("<span class='notice'>The [name] looks at [target.name] with hungry eyes.</span>")

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

@@ -230,6 +230,8 @@
 	if (T && AIStatus == AI_Z_OFF)
 		SSidlenpcpool.idle_mobs_by_zlevel[T.z] -= src
 
+	//Walking counts as a reference, putting this here because most things don't walk, clean this up once walk() procs are dead
+	walk(src, 0)
 	return ..()
 
 /mob/living/simple_animal/vv_edit_var(var_name, var_value)

code/modules/power/gravitygenerator.dm

@@ -34,6 +34,10 @@ GLOBAL_LIST_EMPTY(gravity_generators) // We will keep track of this by adding ne
 	. = ..()
 	soundloop = new(list(src), TRUE)
 
+/obj/machinery/gravity_generator/main/Destroy()
+	. = ..()
+	QDEL_NULL(soundloop)
+
 /obj/machinery/gravity_generator/safe_throw_at(atom/target, range, speed, mob/thrower, spin = TRUE, diagonals_first = FALSE, datum/callback/callback, force = MOVE_FORCE_STRONG, gentle = FALSE)
 	return FALSE
 

code/modules/swarmers/swarmer_act.dm

@@ -114,17 +114,17 @@
 		//Check for dangerous pressure differences
 		if (turf_in_range.return_turf_delta_p() > DANGEROUS_DELTA_P)
 			to_chat(actor, "<span class='warning'>Destroying this object has the potential to cause an explosive pressure release. Aborting.</span>")
-			actor.target = null
+			actor.LoseTarget()
 			return TRUE
 		//Check if breaking this door will expose the station to space/planetary atmos
 		else if(turf_in_range.is_nearby_planetary_atmos() || isspaceturf(turf_in_range) || (!isonshuttle && (istype(turf_area, /area/shuttle) || istype(turf_area, /area/space))) || (isonshuttle && !istype(turf_area, /area/shuttle)))
 			to_chat(actor, "<span class='warning'>Destroying this object has the potential to cause a hull breach. Aborting.</span>")
-			actor.target = null
+			actor.LoseTarget()
 			return FALSE
 		//Check if this door is important in supermatter containment
 		else if(istype(turf_area, /area/engineering/supermatter))
 			to_chat(actor, "<span class='warning'>Disrupting the containment of a supermatter crystal would not be to our benefit. Aborting.</span>")
-			actor.target = null
+			actor.LoseTarget()
 			return FALSE
 	actor.dis_integrate(src)
 	return TRUE
@@ -201,15 +201,15 @@
 		var/area/turf_area = get_area(turf_in_range)
 		if (turf_in_range.return_turf_delta_p() > DANGEROUS_DELTA_P)
 			to_chat(actor, "<span class='warning'>Destroying this object has the potential to cause an explosive pressure release. Aborting.</span>")
-			actor.target = null
+			actor.LoseTarget()
 			return TRUE
 		else if(turf_in_range.is_nearby_planetary_atmos() || isspaceturf(turf_area) || (!isonshuttle && (istype(turf_area, /area/shuttle) || istype(turf_area, /area/space))) || (isonshuttle && !istype(turf_area, /area/shuttle) ))
 			to_chat(actor, "<span class='warning'>Destroying this object has the potential to cause a hull breach. Aborting.</span>")
-			actor.target = null
+			actor.LoseTarget()
 			return TRUE
 		else if(istype(turf_area, /area/engineering/supermatter))
 			to_chat(actor, "<span class='warning'>Disrupting the containment of a supermatter crystal would not be to our benefit. Aborting.</span>")
-			actor.target = null
+			actor.LoseTarget()
 			return TRUE
 	return ..()
 
@@ -220,15 +220,15 @@
 		var/area/turf_area = get_area(turf_in_range)
 		if (turf_in_range.return_turf_delta_p() > DANGEROUS_DELTA_P)
 			to_chat(actor, "<span class='warning'>Destroying this object has the potential to cause an explosive pressure release. Aborting.</span>")
-			actor.target = null
+			actor.LoseTarget()
 			return TRUE
 		else if(turf_in_range.is_nearby_planetary_atmos() || isspaceturf(turf_in_range) || (!is_on_shuttle && (istype(turf_area, /area/shuttle) || istype(turf_area, /area/space))) || (is_on_shuttle && !istype(turf_area, /area/shuttle)))
 			to_chat(actor, "<span class='warning'>Destroying this object has the potential to cause a hull breach. Aborting.</span>")
-			actor.target = null
+			actor.LoseTarget()
 			return TRUE
 		else if(istype(turf_area, /area/engineering/supermatter))
 			to_chat(actor, "<span class='warning'>Disrupting the containment of a supermatter crystal would not be to our benefit. Aborting.</span>")
-			actor.target = null
+			actor.LoseTarget()
 			return TRUE
 	return ..()