Sjávarpúki, The Wreckoner

Trample
{x}, Pay X life: Draw X cards
Discard a card: Each opponent exiles the top card of their library face down
{t}, Exile the top 20 cards of your library: Search target opponents library for an instant or sorcery card and exile it. You may cast that card
and use mana as though it were mana of any colour to cast it.