Grim Roustabout

Card Name

Grim Roustabout

Mana Cost

1

Type

Creature – Skeleton Warrior

Rarity

Common

rules Text

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.)
1
: Regenerate Grim Roustabout.

Flavor Text

He'll point you to your death row seats.

Legal Formats

Commander, Legacy, Modern, Pauper, Pioneer, Vintage

Not Legal Formats

Alchemy, Brawl, Explorer, Historic, Standard

Rulings

(4/15/2013)
You make the choice to have the creature with unleash enter the battlefield with a +1/+1 counter or not as it's entering the battlefield. At that point, it's too late for a player to respond to the creature spell by trying to counter it, for example.
(4/15/2013)
The unleash ability applies no matter where the creature is entering the battlefield from.
(4/15/2013)
A creature with unleash can't block if it has any +1/+1 counter on it, not just one put on it by the unleash ability.
(4/15/2013)
Putting a +1/+1 counter on a creature with unleash that's already blocking won't remove it from combat. It will continue to block.