Dragonmark Fist( Dragonmarked, p. 138)
The power of your dragonmark lets you deal devastating unarmed strikes.
Improved Unarmed Strike (PH) , any true or aberrant dragonmark,
You can spend 1 action point to automatically deal maximum damage with a unarmed strike. The decision to spend the action point is made after the attack is resolved but before damage is rolled.