ep3_switch_faction_war_sides_war_trigger

ep3_switch_faction_war_sides_war_trigger = {
	# Recipient involved in war
	is_participant = scope:recipient
	# Is a Faction war
	save_temporary_scope_as = faction_war_temp
	primary_attacker.joined_faction.faction_war ?= scope:faction_war_temp
	# Actor and recipient on opposing sides
	trigger_if = {
		limit = { is_defender = scope:recipient }
		is_attacker = scope:actor
		# Recipient must not be an ally of the opposing war leader
		NOT = {
			primary_defender = { is_allied_to = scope:recipient }
		}
	}
	trigger_else = {
		is_defender = scope:actor
		# Recipient must not be an ally of the opposing war leader
		NOT = {
			primary_attacker = { is_allied_to = scope:recipient }
		}
	}
	# Recipient must not be a war leader
	NOT = { is_war_leader = scope:recipient }
	# Recipient must not be the claimant
	primary_attacker.joined_faction.special_character != scope:recipient
}

As written in game/common/scripted_triggers/07_ep3_triggers.txt.