Nisos, Titan of Fate's Discord

When Nisos enters the battlefield, sacrifice it unless it escaped.
Whenever Nisos enters the battlefield or attacks,
put the top five cards of target player's library into
their graveyard, then you may exile a target card
from their graveyard.
Escape — {u}{u}{b}{b}, Exile five other cards from
your graveyard. (You may cast this card from your graveyard for its escape cost.)