create_artifact_throne_effect

create_artifact_throne_effect = {
	# Get the character the artifact is being made for.
	$OWNER$ = { save_scope_as = owner }
	$MAKER$ = { save_scope_as = maker }
	hidden_effect_new_object = {
		# Get artifact quality, wealth, and materials
		get_artifact_quality_effect = yes
		get_artifact_wealth_effect = yes

		# Create the artifact
		scope:owner = {
			create_artifact = {	
				name = artifact_throne_name
				description = placeholder # Will be regenerated in the post-creation effects
				creator = scope:maker
				visuals = throne
				type = throne
				modifier = artifact_placeholder_modifier
				save_scope_as = newly_created_artifact
				wealth = scope:wealth
				quality = scope:quality
				#decaying = no
			}
		}
		scope:newly_created_artifact = {
			set_artifact_description = artifact_throne_description
			
			#Let's add modifiers!
			add_scaled_artifact_modifier_prestige_effect = yes
			if = {
				limit = { rarity = illustrious }
				add_scaled_artifact_modifier_majesty_effect = yes
				add_scaled_artifact_modifier_rulership_effect = yes
			}
			else_if = {
				limit = { rarity = famed }
				add_scaled_artifact_modifier_majesty_effect = yes
			}
			
			# All thrones have a chance to get some extra Grandeur
			add_scaled_artifact_modifier_grandeur_big_effect = yes
			remove_artifact_modifier = artifact_placeholder_modifier
		}
	}
}

As written in game/common/scripted_effects/01_ep1_court_artifact_creation_effects.txt.