intrigue_duel_on_attack_effect

intrigue_duel_on_attack_effect = {
	scope:attacker = {
		if = {
			limit = {
				has_character_flag = intrigue_duel_on_attack
			}
			duel = {
				skill = intrigue
				value = scope:defender.intrigue
				50 = {
					compare_modifier = {
						value = scope:duel_value
						multiplier = 3.5
						min = -49
					}
					desc = intrigue_duel_on_attack_effect.success
					send_interface_toast = {
						title = armies_hampered
						left_icon = scope:attacker
						right_icon = scope:defender
						scope:defender = {
							add_character_modifier = {
								modifier = hampered_by_false_information_modifier
								years = 5
							}
						}
					}
					hidden_effect = {
						show_as_tooltip = {
							send_interface_toast = {
								title = armies_hampered
								left_icon = scope:attacker
								right_icon = scope:defender
								scope:defender = {
									add_character_modifier = {
										modifier = hampered_by_false_information_modifier
										years = 5
									}
								}
							}
						}
					}
				}
				50 = {
					compare_modifier = {
						value = scope:duel_value
						multiplier = -3.5
						min = -49
					}
					desc = intrigue_duel_on_attack_effect.failure
					send_interface_toast = {
						title = armies_unhampered
						left_icon = scope:attacker
						right_icon = scope:defender
					}
				}
			}
		}
	}
}

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