Meet the Sword of Apocalypse. Darkness Oathbreaker!
This card gets Power+2000 for each 《Black Dragon》 on your field. [Call Cost] [Pay 1 life] "Darkness Oathbreaker" When this card appears on the field, you may pay 2 gauge. If you do, draw a card, call up to one "Buster" from your hand without paying its [Call Cost], and it gets size-2 and Power+5000 until end of turn. If you called, destroy one card on your opponent's field.