Duchy of St. Cuthbert: Trained at the Steel Chateau Feat for 13th Age

The Steel Chateau is one of the continent's premiere schools of battle and has produced numerous famous warriors in the last three decades.  The school was built on the southeast edge of the Elder Forest.  The site of the school and the wood it was built with were freely given by the wood elves of the Forest for services rendered by Clarissa St. Joan, the Chateau's founder.

Trained at the Steel Chateau

Adventurer Tier: Twice per day, as an interrupt action, you may
   add the escalation die to your miss damage and the target
   becomes vulnerable until the end of their next turn.

Champion Tier: Twice per day, as an interrupt action, you may add
   the escalation die to your AC for that attack only.

Epic Tier: Twice per day, as an interrupt action, you may add
   the escalation die to your AC and PD until the end of your next
   turn.