Korra, Rob's Hellhound

Unleash (You may have this creature enter the battlefield with a +1/+1 counter on it. It can't block as long as it has a +1/+1 counter on it.)

Other Dogs you control have unleash.

Creatures you control with counters on them have haste.

Whenever Korra, Rob's Hellhound attacks, add {r} for each attacking creature