game_rule_random_ruler_placement_effect

game_rule_random_ruler_placement_effect = {
	every_ruler = {
		limit = {
			save_temporary_scope_as = ruler_for_list
			NOR = {
				is_ai = no
				any_liege_or_above = {
					is_ai = no
					dynasty = scope:ruler_for_list.dynasty
				}
			}
		}

		if = {
			limit = { highest_held_title_tier = tier_barony }
			add_to_list = random_placement_barons
		}
		else_if = {
			limit = { highest_held_title_tier = tier_county }
			add_to_list = random_placement_counts
		}
		else_if = {
			limit = { highest_held_title_tier = tier_duchy }
			add_to_list = random_placement_dukes
		}
		else = {
			add_to_list = random_placement_emperors_kings
		}
	}


	### BARONS SHUFFLE ###
	game_rule_random_ruler_placement_shuffle_list_effect = { LIST_NAME = random_placement_barons }
	
	### COUNTS SHUFFLE ###
	game_rule_random_ruler_placement_shuffle_list_effect = { LIST_NAME = random_placement_counts }

	### DUKES SHUFFLE ###
	game_rule_random_ruler_placement_shuffle_list_effect = { LIST_NAME = random_placement_dukes }

	### EMPERORS AND KINGS SHUFFLE ###
	game_rule_random_ruler_placement_shuffle_list_effect = { LIST_NAME = random_placement_emperors_kings }
	
	### MAKE EXCLAVES INDEPENDENT ###
	every_ruler = {
		limit = {
			top_liege != this
			save_temporary_scope_as = exclave_check
			NOT = {
				any_held_title = {
					title_tier = county
					any_neighboring_county = {
						holder = {
							NOR = {
								this = scope:exclave_check
								target_is_liege_or_above = scope:exclave_check
							}
							top_liege = scope:exclave_check.top_liege
						}
					}
				}
			}
		}

		create_title_and_vassal_change = {
			type = independency
			save_scope_as = change
			add_claim_on_loss = no
		}
		becomes_independent = {
			change = scope:change
		}

		resolve_title_and_vassal_change = scope:change
	}
}

As written in game/common/scripted_effects/00_game_rule_effects.txt.