convert_at_war_interaction_effect

convert_at_war_interaction_effect = {
	scope:puppet_or_actor = {
		save_scope_as = convert_at_war
		every_character_war = {
			limit = {
				primary_defender = scope:puppet_or_actor
				primary_attacker = scope:recipient
				using_non_ghw_holy_war_cb_trigger = yes
			}
			set_variable = {
				name = invalidate_defender_faith_change #This variable will invalidate the war and send proper invalidation message
				value = yes
			}
			show_as_tooltip = { end_war = invalidated }
		}

		faith = { save_scope_as = old_faith }
		rite = { save_scope_as = old_rite }

		if = {
			limit = {
				NOT = { rite = scope:recipient.rite }
			}
			convert_to_rite_with_consequences_effect = { RITE = scope:recipient.rite }
			trigger_event = faith_conversion.0003
		}
		
		stress_and_fulfillment_impact = {
			zealous = medium_stress_impact_gain
		}
	}
	scope:recipient = {
		add_piety_experience = major_piety_value
	}
}

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