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Gnawing Assault
Ranger Attack 19

your beast companion clamps down on a foe and rends its flesh.

Melee beast 1

Target: One creature

Attack: Beast's attack bonus vs. AC

Hit: 2[B] + beast's Strength modifier damage, and the target is immobilized (save ends).

Miss: Half damage, and the target is immobilized until the end of its next turn.

Effect: If the target was already immobilized and your beast companion began the turn adjacent to it, the target takes ongoing 10 damage (save ends).

Gnawing Assault is a daily power available to rangers at the 19th level.[MP:54]