Challenge for Artifact

is_available = trigger_if = {
	limit = {
		is_ai = yes
	}
	has_outstanding_artifact_claims = yes
	ai_greed >= low_negative_ai_value
	can_start_single_combat_trigger = yes
	is_imprisoned = no
	NOT = {
		has_trait = craven
	}
}
is_shown = scope:actor != scope:recipient
custom_description = {
	text = challenge_for_artifact_interaction_valid_tt_1
	scope:recipient = {
		any_character_artifact = {
			can_be_claimed_by = scope:actor
			NOT = {
				has_variable = is_tribute_mission_artifact
			}
		}
	}
}
scope:recipient = {
	trigger_if = {
		limit = {
			exists = involved_activity
		}
		NOT = {
			involved_activity ?= {
				has_activity_type = activity_coronation
				activity_host ?= scope:recipient
			}
		}
	}
}

As written in game/common/character_interactions/00_artifact_interactions.txt.

rival_single_combat_shown_and_not_invalid_trigger = yes
scope:recipient = {
	can_start_single_combat_trigger = yes
}
scope:recipient = {
	custom_description = {
		text = fp1_tbc_recipient_banned_from_combat
		can_start_single_combat_banned_checks_trigger = no
	}
}
scope:recipient = {
	is_imprisoned = no
}
scope:actor = {
	is_imprisoned = no
}
scope:actor = {
	custom_description = {
		text = character_interactions_hostile_actions_disabled_delay
		NOT = {
			has_character_flag = flag_hostile_actions_disabled_delay
		}
	}
}

As written in game/common/character_interactions/00_artifact_interactions.txt.

on_send = scope:actor = {
	add_character_flag = {
		flag = flag_hostile_actions_disabled_delay
		days = 10
	}
}
on_accept = scope:actor = {
	remove_character_flag = flag_hostile_actions_disabled_delay
}
scope:actor = {
	custom_tooltip = challenge_to_single_combat_interaction.enter_non_lethal_bout.tt
	custom_tooltip = challenge_to_artifact_combat_interaction_victor_gets.tt
	custom_tooltip = challenge_to_artifact_combat_interaction_loser_gets.tt
}
configure_start_single_combat_effect = {
	SC_INITIATOR = scope:actor
	SC_ATTACKER = scope:actor
	SC_DEFENDER = scope:recipient
	FATALITY = no
	FIXED = no
	LOCALE = terrain_scope
	OUTPUT_EVENT = artifact.2001
	INVALIDATION_EVENT = fp1_tbc.0021
}
add_clan_unity_interaction_effect = {
	CHARACTER = scope:actor
	TARGET = scope:recipient
	VALUE = major_unity_loss
	DESC = clan_unity_challenge_artifact.desc
	REVERSE_NON_HOUSE_TARGET = no
}
on_decline = add_clan_unity_interaction_effect = {
	CHARACTER = scope:actor
	TARGET = scope:recipient
	VALUE = minor_unity_gain
	DESC = clan_unity_challenge_artifact_refusal.desc
	REVERSE_NON_HOUSE_TARGET = no
}
scope:actor = {
	send_interface_toast = {
		type = event_toast_effect_neutral
		title = challenge_to_single_combat_interaction.challenge_rejected.t
		left_icon = scope:recipient
		right_icon = scope:actor
		scope:recipient = {
			add_prestige = {
				value = 0
				subtract = challenge_for_artifact_prestige_cost_value
			}
		}
		show_as_tooltip = {
			add_prestige = challenge_for_artifact_prestige_cost_value
		}
	}
	hidden_effect = {
		add_prestige_no_experience = challenge_for_artifact_prestige_cost_value
		remove_interaction_cooldown = challenge_for_artifact_interaction
	}
	if = {
		limit = {
			has_character_flag = flag_hostile_actions_disabled_delay
		}
		remove_character_flag = flag_hostile_actions_disabled_delay
	}
}

As written in game/common/character_interactions/00_artifact_interactions.txt.