Just another idea to float out there:

Perhaps have the WF capstone give them Divine Sacrifice 1 as an ability.

Quote Originally Posted by DDO Compendium
Giving up some of your life force to win the battle, you empower your next blow against your foe. This attack deals an additional 5 to 30 Light damage and increases the critical multiplier of your weapon by 1, but costs you 5 hp and 1 sp, whether or not the attack is successful.\n\nD&D Dice: Deals 5d6 light damage.