adventurer_realm_destabilisation_civil_war_effect

adventurer_realm_destabilisation_civil_war_effect = {
	$TITLE_GIVER$ = { save_scope_as = ruler }
	$TITLE_RECEIVER$ = { save_scope_as = adventurer }
	$TITLE$ = { save_scope_as = title }
	if = {
		limit = {
			any_in_list = { list = independent_vassals }
		}
		scope:ruler = {
			if = {
				limit = { is_alive = yes }
				save_scope_as = claimant
			}
			else_if = {
				limit = {
					any_in_list = { list = heirs }
				}
				random_in_list = {
					list = heirs
					limit = { has_strong_claim_on = scope:realm }
					alternative_limit = { has_weak_claim_on = scope:realm }
					weight = {
						base = 1
						modifier = { add = age }
					}
					save_scope_as = claimant
				}
			}
			else_if = {
				limit = {
					scope:title = {
						any_claimant = {
							this != scope:adventurer
						}
					}
				}
				scope:title = {
					random_claimant = {
						limit = { has_strong_claim_on = scope:realm }
						alternative_limit = { has_weak_claim_on = scope:realm }
						weight = {
							base = 1
							modifier = { add = age }
						}
						save_scope_as = claimant
					}
				}
			}
			else = {
				ordered_in_list = {
					list = independent_vassals
					order_by = max_military_strength
					save_scope_as = claimant
				}
			}
		}
		# Vassals Breakaway
		ordered_in_list = {
			list = independent_vassals
			limit = {
				can_create_faction = {
					type = claimant_faction
					target = scope:adventurer
				}
			}
			order_by = max_military_strength
			save_scope_as = revolt_leader
			create_faction = {
				type = claimant_faction
				target = scope:adventurer
			}
			joined_faction = {
				save_scope_as = faction
				set_special_character = scope:claimant
				set_special_title = scope:realm
			}
		}
		every_in_list = {
			list = independent_vassals
			limit = {
				this != scope:revolt_leader
				can_join_faction = scope:faction
			}
			join_faction = scope:faction
		}
		scope:faction = {
			faction_start_war = { title = scope:realm }
		}
	}
}

As written in game/common/scripted_effects/07_dlc_ep3_scripted_effects.txt.