claim_throne_check_target_title_effect

claim_throne_check_target_title_effect = {
	# In case something has happened to the target_title, we try to reset it here:
	if = {
		limit = {
			OR = {
				NOT = { exists = scope:target_title } # The title could somehow disappear
				NOT = {
					scope:target_title = { # The title might feasibly pass to someone else
						holder ?= scope:target

					}
				}
			}
		}
		scope:target = {
			primary_title = { # We just assign the target's primary title as the new target title
				save_scope_as = target_title
			}
		}
	}

	# Rivalry check is done here, since it's run in every outcome
	if = {
		limit = {
			OR = {
				exists = scope:scheme_successful
				exists = scope:scheme_discovered
			}
			NOT = { has_relation_rival = scope:target }
		}
		hidden_effect = {
			random = {
				chance = 30
				modifier = {
					add = 30
					has_relation_potential_rival = scope:target
				}
				modifier = {
					exists = scope:scheme_discovered
					add = 30
				}
				modifier = {
					has_relation_friend = scope:target
					add = -25
				}

				save_scope_value_as = {
					name = set_rivalry
					value = yes
				}
			}
		}
	}
}

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