Screean, the Ancient

Flying, Deathtouch
At the beginning of each opponents turn, create 1 trinket token for each land they have untapped
If mana would empty from an opponents mana
pool without being spent, create that many
trinket tokens
Sacrifice 8 trinket tokens: Search your library for
a card and put it into your hand, then shuffle
your library
Sacrifice 10 trinket tokens: Cast target card from
your hand without paying its mana cost.