Slithre, the Quiet

Flying, haste
Groundbreaker ({0}: This creature loses flying until
end of turn and cannot be blocked this turn. Use this ability only once per game)
Whenever Slithre, the Quiet attacks and isn't
blocked you may pay {x}{u/b} if you do look at the
top X cards of your library and put two of them
into your hand. Put the rest on the bottom of
your library in any order.