Roham, Tempest Emeritus

Whenever Roham, Tempest Emeritus attacks, exile the top card of each player's library. Whenever a permanent card is exiled this way, add {u} or {r}. Until end of turn, you don't lose this mana as steps and phases end. Whenever an instant or sorcery card is exiled this way, each player may pay {1}. Each player that does may copy that spell and they may cast the copy without