Lucario

When Lucario deals combat damage to a player,
put an aura counter on target creature, then you
may destroy target creature with an aura counter
on it.
When Lucario is dealt damage, put an aura
counter on it.
If there are three or more aura counters on creatures, Lucario has double strike, otherwise
it has first strike.
Lucario has +1/+1 for each aura counter on it.
Ninjutsu {2}{u}{r}