Scaling cap of sentient zombies to alive marines

code/__DEFINES/zombie.dm

@@ -12,3 +12,5 @@
 #define ZOMBIE_THREATENED_CAP 125
 ///How much damage zombies take from razorwire
 #define ZOMBIE_RAZORWIRE_DAMAGE 50
+///The ratio of maximum allowed possessed sentient zombies to alive humans
+#define ZOMBIE_SENTIENT_TO_HUMAN_RATIO 7

code/_globalvars/lists/mobs.dm

@@ -34,6 +34,7 @@ GLOBAL_LIST_INIT(simple_animals, list(list(),list(),list(),list())) // One for e
 GLOBAL_LIST_EMPTY(living_cameras)
 GLOBAL_LIST_EMPTY(aiEyes)
 GLOBAL_LIST_EMPTY_TYPED(humans_by_zlevel, /list/mob/living/carbon/human)			//z level /list/list of alive humans
+GLOBAL_LIST_EMPTY(possessed_sentient_zombie_list)
 
 GLOBAL_LIST_EMPTY(mob_config_movespeed_type_lookup)
 

code/_globalvars/misc.dm

@@ -38,3 +38,6 @@ GLOBAL_PROTECT(key_to_time_of_strain_swap)
 
 ///List of ssd living mobs
 GLOBAL_LIST_EMPTY(ssd_living_mobs)
+
+///Maximum allowed number of possessed sentient zombies
+GLOBAL_VAR_INIT(maximum_allowed_possessed_zombies, 0)

code/datums/actions/observer_action.dm

@@ -63,6 +63,11 @@
 	if(new_mob.stat == DEAD)
 		to_chat(owner, span_warning("You cannot join if the mob is dead."))
 		return FALSE
+
+	if(iszombie(new_mob) && (length(GLOB.possessed_sentient_zombie_list) >= GLOB.maximum_allowed_possessed_zombies))
+		to_chat(owner, span_warning("There are too few marines. Possessing additional zombies is currently disabled."))
+		return FALSE
+
 	if(tgui_alert(owner, "Are you sure you want to take " + new_mob.real_name +" ("+new_mob.job.title+")?", "Take SSD mob", list("Yes", "No",)) != "Yes")
 		return
 
@@ -94,6 +99,8 @@
 
 	message_admins(span_adminnotice("[owner.key] took control of [new_mob.name] as [new_mob.p_they()] was ssd."))
 	log_admin("[owner.key] took control of [new_mob.name] as [new_mob.p_they()] was ssd.")
+	if(iszombie(new_mob))
+		GLOB.possessed_sentient_zombie_list += new_mob
 	var/mob/living/carbon/human/new_human = new_mob
 	var/datum/job/j = new_human.job
 	var/datum/outfit/job/o = j.outfit

code/datums/gamemodes/zombie_crash.dm

@@ -111,6 +111,9 @@
 	var/list/living_player_list = count_humans_and_zombies(count_flags = COUNT_IGNORE_HUMAN_SSD)
 	var/num_humans = living_player_list[1]
 	var/num_zombies = living_player_list[2]
+
+	GLOB.maximum_allowed_possessed_zombies = floor(num_humans / ZOMBIE_SENTIENT_TO_HUMAN_RATIO)
+
 	if(num_zombies * 0.125 >= num_humans) // if there's too much zombies, don't spawn even more
 		for(var/obj/effect/ai_node/spawner/zombie/spawner AS in GLOB.zombie_spawners)
 			if(!spawner.threat_warning)

code/modules/mob/dead/observer/observer.dm

@@ -288,6 +288,7 @@ GLOBAL_VAR_INIT(observer_default_invisibility, INVISIBILITY_OBSERVER)
 	. = ..()
 	if(!. || can_reenter_corpse)
 		return
+	GLOB.possessed_sentient_zombie_list -= src
 	var/mob/ghost = .
 	GLOB.key_to_time_of_death[ghost.key] = world.time
 	if(!aghosting && job?.job_flags & (JOB_FLAG_LATEJOINABLE|JOB_FLAG_ROUNDSTARTJOINABLE))//Only some jobs cost you your respawn timer.

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

@@ -291,6 +291,14 @@
 /datum/species/proc/handle_death(mob/living/carbon/human/H)
 	return
 
+///Handles any species-specific gib events
+/datum/species/proc/handle_gib(mob/living/carbon/human/H)
+	return
+
+///Handles any species-specific dusting events
+/datum/species/proc/handle_dust(mob/living/carbon/human/H)
+	return
+
 ///Called in revival procs, useful for special species behaviour like zombie revival
 /datum/species/proc/can_revive_to_crit(mob/living/carbon/human/H)
 	if(H.has_working_organs())

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

@@ -13,6 +13,7 @@
 		if(prob(100 - E.get_damage()))
 			// Override the current limb status
 			E.droplimb(gibbing = TRUE, silent = TRUE)
+	species.handle_gib(src)
 	return ..()
 
 /mob/living/carbon/human/gib_animation()
@@ -27,6 +28,9 @@
 		hgibs(loc)
 		new /obj/effect/temp_visual/gib_particles(get_turf(src), get_blood_color())
 
+/mob/living/carbon/human/dust()
+	species.handle_dust(src)
+	. = ..()
 
 
 /mob/living/carbon/human/spawn_dust_remains()

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

@@ -123,6 +123,14 @@
 		return
 	addtimer(CALLBACK(H, TYPE_PROC_REF(/mob/living/carbon/human, revive_to_crit), TRUE, FALSE), revive_time)
 
+/datum/species/zombie/handle_gib(mob/living/carbon/human/H)
+	. = ..()
+	GLOB.possessed_sentient_zombie_list -= H
+
+/datum/species/zombie/handle_dust(mob/living/carbon/human/H)
+	. = ..()
+	GLOB.possessed_sentient_zombie_list -= H
+
 /datum/species/zombie/can_revive_to_crit(mob/living/carbon/human/human)
 	if(human.on_fire || !human.has_working_organs() || isspaceturf(get_turf(human)))
 		SSmobs.stop_processing(human)
@@ -133,6 +141,7 @@
 /// We start fading out the human and qdel them in set time
 /datum/species/zombie/proc/fade_out_and_qdel_in(mob/living/carbon/human/H, time = 5 SECONDS)
 	GLOB.round_statistics.zombies_permad++
+	GLOB.possessed_sentient_zombie_list -= H
 	fade_out(H)
 	QDEL_IN(H, time)
 

code/modules/mob/living/living.dm

@@ -638,6 +638,10 @@ below 100 is not dizzy
 			to_chat(M, span_warning("You are jobbanned from that role."))
 			return FALSE
 
+		if(iszombie(src) && (length(GLOB.possessed_sentient_zombie_list) >= GLOB.maximum_allowed_possessed_zombies))
+			to_chat(M, span_warning("There are too few marines. Possessing additional zombies is currently disabled."))
+			return FALSE
+
 		log_game("[key_name(M)] has taken over [key_name_admin(src)].")
 		message_admins("[key_name_admin(M)] has taken over [ADMIN_TPMONTY(src)].")
 

code/modules/mob/living/living_health_procs.dm

@@ -412,6 +412,8 @@
 		if(!iszombie(src))
 			set_species("Strong zombie")
 		AddComponent(/datum/component/ai_controller, /datum/ai_behavior/xeno/zombie/patrolling)
+		if(client && !(src in GLOB.possessed_sentient_zombie_list))
+			GLOB.possessed_sentient_zombie_list += src
 	heal_limbs(-health)
 	set_stat(CONSCIOUS)
 	overlay_fullscreen_timer(0.5 SECONDS, 10, "roundstart1", /atom/movable/screen/fullscreen/black)