Fogmist Elemental

Guidance - {1}{u}, Exile Fogmist Elemental from
your hand: Target player puts the top five cards
of their library into their graveyard.
When Fogmist Elemental enters the battlefield,
target player puts the top ten cards of their
graveyard into their library.
As long a graveyard has twenty or more cards in
it, you may cast Fogmist Elemental from exile.