When Nicol Bolas, the Ravager enters the battlefield, each opponent discards a card.
4UBR: Exile Nicol Bolas, the Ravager, then return him to the battlefield transformed under his owner's control. Activate this ability only any time you could cast a sorcery.
Nicol Bolas, the Arisen 
[+2]: Draw two cards.
[-3]: Nicol Bolas, the Arisen deals 10 damage to target creature or planeswalker.
[-4]: Put target creature or planeswalker card from a graveyard onto the battlefield under your control.
[-12]: Exile all but the bottom card of target player's library.