Raging Bloodcut

Heroic Tier
Prerequisite: Barbarian
Benefit: When you hit a target with any rage power, you have the option of reducing the damage to that target by 1[W] before you roll damage. If you do so, the target takes ongoing 5 damage (save ends).
At 11th level, you gain the option of reducing the damage by 2[W] to increase the ongoing damage to 10. At 21st level, you gain the option of reducing the damage by 3[W] to increase the ongoing damage to 15. You can’t take away more damage dice than the power has. For example, if a power normally deals 2[W] damage, you can’t reduce the damage by 3[W].

Published in Primal Power, page(s) 141.