The Knight

Persist (When it dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with
a -1/-1 counter on it.)
{w}{w}: Put a +1/+1 counter on the Knight, it gains
first strike until the end of turn.
{b}{b}: The Knight gains shadow until the end of
turn. (It can block or be blocked by only creatures
with shadow.)