Goblin Tunneler

{T}: Target creature with power 2 or less can't be blocked this turn.

Arena Beginner Set

"The best way over the mountain is through."

Duel Decks: Merfolk vs. Goblins

Conspiracy: Take the Crown

Magic 2012

{T}: Target creature with power 2 or less is unblockable this turn.

"You never know what's going to be in goblin tunnels. Even in the best case, there will still be goblins."
—Sachir, Akoum Expeditionary House

Magic 2011

The ability doesn’t grant an ability to the targeted creature. Rather, it affects the game rules and states something that’s now true about that creature. After the ability resolves, the creature can’t be blocked that turn even if it loses all abilities.

The power of the targeted creature is checked both as you target it and as the ability resolves. After the ability resolves, the creature can’t be blocked that turn even if its power becomes greater than 2.