原文A creature has been dealt excess damage if Nahiri's Warcrafting deals more damage to it than the minimum amount of damage required to be lethal damage. In most cases, this means damage greater than the creature's toughness, but consider any damage that was already dealt to it that turn.
原文For a planeswalker, excess damage means damage in excess of the planeswalker's loyalty (the number of loyalty counters it has on it). For a battle, excess damage means damage in excess of the battle's defense (the number of defense counters it has on it).
原文Playing the exiled card follows the normal rules for playing that card. You must pay its cost, and you must follow all applicable timing rules. For example, if it's a creature card, you can cast it by paying its mana cost only during your main phase while the stack is empty.