Cerebro

When a blue creature enters the battlefield under
your control, you may attach Cerebro to it.
Equipped creature has hexproof and "{t}:Look at
the top 10 cards of your library. You may choose
a human creature from among these cards and
put it into your hand. Put the rest on the bottom
of your library."
If you control 6 or more human creatures,
equipped creature has "{t}: Creatures you control
gain hexproof and prowess until end of turn."
Equip {2}