Farlan Mana-Knight

Hexproof, Infiltrate (At the beginning of your combat step, you may tap this creature. If you do, another target creature with power lower than this creature without a +1/+1 counter is unblockable until the end of turn. Put a +1/+1 counter on it.).
Creatures you control with a +1/+1 counter on them gain Hexproof.