diff --git a/code/game/gamemodes/dynamic/antag_rulesets.dm b/code/game/gamemodes/dynamic/antag_rulesets.dm
index 3e56784bdbb..500f9aa419f 100644
--- a/code/game/gamemodes/dynamic/antag_rulesets.dm
+++ b/code/game/gamemodes/dynamic/antag_rulesets.dm
@@ -49,6 +49,8 @@
 	var/antag_amount = 0
 	/// All of the minds that we will make into our antagonist type
 	var/list/datum/mind/pre_antags = list()
+	/// If non-zero, how long from the start of the game should a latespawn for this role occur?
+	var/latespawn_time
 
 /datum/ruleset/Destroy(force, ...)
 	stack_trace("[src] ([type]) was destroyed.")
@@ -63,7 +65,7 @@
 /datum/ruleset/proc/antagonist_possible(budget)
 	return budget >= antag_cost
 
-/datum/ruleset/proc/pre_setup()
+/datum/ruleset/proc/roundstart_pre_setup()
 	if(antag_amount == 0)
 		return
 	if(antag_amount < 0)
@@ -81,7 +83,7 @@
 	for(var/datum/mind/antag as anything in possible_antags)
 		if(antag_amount <= 0)
 			break
-		if(!can_apply(antag))
+		if(!roundstart_can_apply(antag))
 			continue
 		pre_antags += antag
 		if(assign_job_role)
@@ -94,7 +96,7 @@
 		refund("Missing [antag_amount] antagonists for [src] ruleset.")
 		return antag_cost * antag_amount // shitty refund for now
 
-/datum/ruleset/proc/can_apply(datum/mind/antag)
+/datum/ruleset/proc/roundstart_can_apply(datum/mind/antag)
 	if(EXCLUSIVE_OR(antag.current.client.prefs.active_character.species in banned_species, banned_species_only))
 		SEND_SIGNAL(src, COMSIG_RULESET_FAILED_SPECIES)
 		return FALSE
@@ -102,7 +104,7 @@
 		return FALSE
 	return TRUE
 
-/datum/ruleset/proc/post_setup(datum/game_mode/dynamic)
+/datum/ruleset/proc/roundstart_post_setup(datum/game_mode/dynamic)
 	for(var/datum/mind/antag as anything in pre_antags)
 		antag.add_antag_datum(antagonist_type)
 
@@ -113,6 +115,47 @@
 	// Currently unimplemented. Will be useful for a possible future PR where latejoin antagonists are factored in.
 	return
 
+/datum/ruleset/proc/get_latejoin_players()
+	var/list/candidates = list()
+
+	// Assemble a list of active players without jobbans.
+	for(var/mob/living/carbon/human/player in GLOB.player_list)
+		// Has a mind
+		if(!player.mind)
+			continue
+		// Connected and not AFK
+		if(!player.client || (locate(player) in SSafk.afk_players))
+			continue
+		// Not antag-banned and not specific antag banned
+		if(jobban_isbanned(player, ROLE_SYNDICATE) || jobban_isbanned(player, antagonist_type::job_rank))
+			continue
+		// Make sure they want to play antag, and that they're not already something (off station or antag)
+		if(player.client.skip_antag || player.mind.offstation_role || player.mind.special_role)
+			continue
+		// Make sure they actually want to be this antagonist
+		if(!(antagonist_type::job_rank in player.client.prefs.be_special))
+			continue
+		// Make sure their species CAN be this antagonist
+		if(EXCLUSIVE_OR(player.dna.species.name in banned_species, banned_species_only))
+			continue
+		// Make sure they're not in a banned job
+		if(player.mind.assigned_role in banned_jobs)
+			continue
+
+		candidates += player.mind
+
+	return shuffle(candidates)
+
+/datum/ruleset/proc/latespawn(datum/game_mode/dynamic/dynamic)
+	// latespawning is only used by traitors at this point, so we're just going to be naive and allocate all budget when this proc is called.
+	var/late_antag_amount = floor(dynamic.budget_overflow / antag_cost)
+	dynamic.budget_overflow -= (late_antag_amount * antag_cost)
+
+	var/list/datum/mind/possible_antags = get_latejoin_players()
+	for(var/i in 1 to late_antag_amount)
+		var/datum/mind/antag = pick_n_take(possible_antags)
+		antag.add_antag_datum(antagonist_type)
+
 /datum/ruleset/traitor
 	name = "Traitor"
 	ruleset_weight = 11
@@ -120,15 +163,14 @@
 	antag_weight = 2
 	antagonist_type = /datum/antagonist/traitor
 
-/datum/ruleset/traitor/post_setup(datum/game_mode/dynamic)
-	var/random_time = rand(5 MINUTES, 15 MINUTES)
+/datum/ruleset/traitor/roundstart_post_setup(datum/game_mode/dynamic)
+	latespawn_time = rand(5 MINUTES, 15 MINUTES)
 	for(var/datum/mind/antag as anything in pre_antags)
 		var/datum/antagonist/traitor/traitor_datum = new antagonist_type()
 		if(ishuman(antag.current))
 			traitor_datum.delayed_objectives = TRUE
-			traitor_datum.addtimer(CALLBACK(traitor_datum, TYPE_PROC_REF(/datum/antagonist/traitor, reveal_delayed_objectives)), random_time, TIMER_DELETE_ME)
+			traitor_datum.addtimer(CALLBACK(traitor_datum, TYPE_PROC_REF(/datum/antagonist/traitor, reveal_delayed_objectives)), latespawn_time, TIMER_DELETE_ME)
 		antag.add_antag_datum(traitor_datum)
-	addtimer(CALLBACK(dynamic, TYPE_PROC_REF(/datum/game_mode, fill_antag_slots)), random_time)
 
 /datum/ruleset/vampire
 	name = "Vampire"
diff --git a/code/game/gamemodes/dynamic/dynamic.dm b/code/game/gamemodes/dynamic/dynamic.dm
index 1e0e1ec4ad2..dfff3aa7aae 100644
--- a/code/game/gamemodes/dynamic/dynamic.dm
+++ b/code/game/gamemodes/dynamic/dynamic.dm
@@ -3,7 +3,6 @@ GLOBAL_LIST_EMPTY(dynamic_forced_rulesets)
 /datum/game_mode/dynamic
 	name = "Dynamic"
 	config_tag = "dynamic"
-	secondary_restricted_jobs = list("AI")
 	required_players = 10
 	/// Non-implied rulesets in play
 	var/list/datum/ruleset/rulesets = list()
@@ -126,7 +125,7 @@ GLOBAL_LIST_EMPTY(dynamic_forced_rulesets)
 
 	for(var/datum/ruleset/ruleset in (rulesets + implied_rulesets)) // rulesets first, then implied rulesets
 		// log_dynamic("Applying [ruleset.antag_amount] [ruleset.name]\s.")
-		budget_overflow += ruleset.pre_setup()
+		budget_overflow += ruleset.roundstart_pre_setup()
 
 	// log_dynamic("Budget overflow: [budget_overflow].")
 	// for the future, maybe try readding antagonists with apply_antag_budget(budget_overflow)
@@ -137,13 +136,11 @@ GLOBAL_LIST_EMPTY(dynamic_forced_rulesets)
 	for(var/datum/ruleset/ruleset in (rulesets + implied_rulesets))
 		// if(length(ruleset.pre_antags))
 		// 	log_dynamic("Making antag datums for [ruleset.name] ruleset.")
-		ruleset.post_setup(src)
+		ruleset.roundstart_post_setup(src)
+		if(ruleset.latespawn_time)
+			addtimer(CALLBACK(ruleset, TYPE_PROC_REF(/datum/ruleset, latespawn), src), ruleset.latespawn_time)
 	..()
 
-/datum/game_mode/dynamic/traitors_to_add()
-	. = floor(budget_overflow / /datum/ruleset/traitor::antag_cost)
-	budget_overflow -= (. * /datum/ruleset/traitor::antag_cost)
-
 /datum/game_mode/dynamic/latespawn(mob)
 	. = ..()
 	budget_overflow++
diff --git a/code/game/gamemodes/game_mode.dm b/code/game/gamemodes/game_mode.dm
index fe838e735d0..d072659317c 100644
--- a/code/game/gamemodes/game_mode.dm
+++ b/code/game/gamemodes/game_mode.dm
@@ -319,7 +319,10 @@
 							//			Less if there are not enough valid players in the game entirely to make recommended_enemies.
 
 // Just the above proc but for alive players
-/// Gets all alive players for a specific role. Disables offstation roles by default
+/**
+ * DEPRECATED!
+ * Gets all alive players for a specific role. Disables offstation roles by default
+ */
 /datum/game_mode/proc/get_alive_players_for_role(role, override_jobbans = FALSE, allow_offstation_roles = FALSE)
 	var/list/players = list()
 	var/list/candidates = list()
@@ -645,6 +648,9 @@
 /datum/game_mode/proc/traitors_to_add()
 	return 0
 
+/**
+ * DEPRECATED!
+ */
 /datum/game_mode/proc/fill_antag_slots()
 	var/traitors_to_add = 0