Clash of King's ability is a Reaction to winning any power challenge, so it can be triggered on both offense and defense.
- The reaction ability is in addition to claim, and occurs at step "D" in the DUCK acronym.
- D for Determine winner - first you determine the winner/loser, the the amount of strength the challenge was won by, and the unopposed/opposed status of the challenge. Then players trigger reactions to winning/losing, like Put to the Sword, Lannisport, and Ghaston Grey.
- U for Unopposed bonus - this is where the attacking claims a power if the challenge is unopposed, and can trigger reactions to claiming the unopposed bonus, like Rise of the Kraken.
- C for Claim - now claim is applied, if any, and players can trigger interrupts to claim like Vengeance for Elia, or reactions like Bastard Daughter dying to military claim or Crone of Vaes Dothrak reacting to intrigue claim.
- K for Keywords - finally, keywords and their reactions happen last. For example, when Robert gains a power for renown, you can trigger Lightbringer.