Attach
The creature can attempt a special attack against KAC as a standard action. If it succeeds, it deals no damage, but the creature adheres to its target. Once attached, the creature gains a +4 bonus to its AC (from cover) and a +2 circumstance bonus to melee attacks, but it can attack only the creature to which it’s attached. An attached creature can’t move on its own (though it moves with its target), take actions that require two hands, or make attacks of opportunity. An attached creature can be removed with a successful Strength check (DC = 10 + 1-1/2 × the creature’s CR) made as a move action, or it can remove itself from its target as a move action.
Format: Melee attach +6.
Source
Alien Archive pg. 152