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Pokemon trading card game: Trainer cards Trainer cards in the Pokmon Trading Card Game offer different advantages and come in three types: Item cards: These are played during your turn, and you can add as many as you want before making an attack

The Ur-Dragon's triggered ability resolves after all attackers have been chosen

It will not overwrite effects that modify power or toughness (whether from a static ability, counters, or a resolved spell or ability), nor will it overwrite effects that set power and toughness which come into existence after the ability resolves

Yes, that card has to be a land, but guess what