Revenant Gamemode (#10851)

Added a new wave defense gamemode, Revenants, wherein the station crew have to defend themselves from an endless wave of humanoid bluespace creatures.

Ported the icon from Baystation, it's their blueforged, but I tweaked the mob's alpha values a tad. Baystation12/Baystation12#21669

code/modules/ghostroles/spawner/antagonist/revenant.dm

@@ -0,0 +1,45 @@
+/datum/ghostspawner/revenant
+	short_name = MODE_REVENANT
+	name = "Revenant"
+	desc = "A creature borne of bluespace, you are here to wreak havoc and put an end to bluespace experimentation, one station at a time."
+	tags = list("Antagonist")
+
+	observers_only = TRUE
+	show_on_job_select = FALSE
+
+	enabled = FALSE
+	landmark_name = "Revenant"
+	max_count = 0
+
+	spawn_mob = /mob/living/carbon/human/revenant
+	respawn_flag = ANIMAL
+
+	var/has_fired = FALSE
+
+/datum/ghostspawner/revenant/spawn_mob(mob/user)
+	var/turf/T = select_spawnlocation()
+	var/mob/living/carbon/human/revenant/R
+	if(T)
+		R = new /mob/living/carbon/human/revenant(T)
+	else
+		to_chat(user, SPAN_WARNING("Unable to find any spawn point."))
+		return
+
+	if(R)
+		announce_ghost_joinleave(user, FALSE, "They are now a [name].")
+		R.ckey = user.ckey
+
+	revenants.add_antagonist(R.mind, TRUE, TRUE, FALSE, TRUE, TRUE)
+	if(!has_fired)
+		INVOKE_ASYNC(src, .proc/play_ambience, R)
+
+	return R
+
+/datum/ghostspawner/revenant/proc/play_ambience(var/mob/living/carbon/human/H)
+	for(var/m in player_list - H)
+		var/mob/M = m
+		if(M.ear_deaf)
+			continue
+		M.playsound_simple(get_turf(M), 'sound/ambience/tension/tension.ogg', 75, FALSE)
+		to_chat(M, FONT_LARGE(SPAN_CULT("A faint hum coming from the station walls fills your ears...")))
+	has_fired = TRUE

code/modules/ghostroles/spawner/atom/borer.dm

@@ -4,6 +4,8 @@
 	desc = "Infest crew, reproduce, repeat."
 	tags = list("Antagonist")
 
+	observers_only = TRUE
+
 	loc_type = GS_LOC_ATOM
 	atom_add_message = "A borer has been birthed!"
 

code/modules/ghostroles/spawner/base.dm

@@ -2,7 +2,10 @@
 	var/short_name = null
 	var/name = null
 	var/desc = null
+
+	var/observers_only = FALSE
 	var/show_on_job_select = TRUE // Determines if the ghost spawner role is considered unique or not.
+
 	var/welcome_message = null
 	var/list/tags = list() //Tags associated with that spawner
 
@@ -71,6 +74,9 @@
 		if(!is_alien_whitelisted(user, req_species_whitelist))
 			return "Missing Species Whitelist"
 
+	if(observers_only && !isobserver(user))
+		return "Observers Only"
+
 	return FALSE
 
 //Return a error message if the user CANT spawn. Otherwise FALSE