Enchant player
(Target a(n) player as you cast this. This card enters the battlefield attached to that player.)
Creatures attacking enchanted player have
trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.).
Whenever a creature deals combat damage to enchanted player, that player exiles the top card of their library. Until end of turn, that creature's controller may play that card and they may spend mana as though it were mana of any color to cast that spell.