The Duke, Rebel Sentry Foil

Legendary Creature — Human Rebel Ally

The Duke enters with a +1/+1 counter on him. , Remove a counter from The Duke: Put a +1/+1 counter on another target creature you control. It gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

A royal pain in the Fire Nation's backside.