process_tour_achievement_tallies_effect

process_tour_achievement_tallies_effect = {
	scope:host = {
		if = {
			limit = {
				exists = global_var:started_the_grandest_tour_achievement
				is_ai = no
				scope:stop_host_scope.highest_held_title_tier >= tier_kingdom
			}
			scope:activity = {
				add_to_variable_list = {
					name = the_grandest_tour_achievement_tally_list
					target = scope:stop_host_scope
				}
			}
		}
		if = {
			limit = {
				exists = global_var:started_imperial_march_achievement
				is_ai = no
				scope:activity = {
					has_activity_option = {
						category = special_type
						option = tour_type_intimidation
					}
				}
				scope:stop_host_scope = { is_powerful_vassal = yes }
			}
			scope:activity = {
				add_to_variable_list = {
					name = imperial_march_achievement_list
					target = scope:stop_host_scope
				}
			}
		}
	}
}

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