|Cause of Death|
|Cause of Death:||Killed by crocodile(s)|
- Hammerclaw first appears when the DiamondClan leader, Nebulastar, comes to the SapphireClan camp to ask for help in fighting RubyClan off their territory. Hammerclaw is seen standing next to his leader.
- Later, at the gathering, Nebulastar reports that crocodiles from the river are attacking DiamondClan, and that the night before Hammerclaw had been killed by them.
- After they save him from Lilypaw, Gaypaw explains to Moonpaw, Screepaw, and Tranquilpaw that Hammerclaw died trying to get a drink.
- "I have an announcement! Crocodiles from the river are attacking DiamondClan! Hammerclaw died last night!"
- —Nebulastar reporting Hammerclaw's death at the gathering Hidden Prophecies, chapter 4
- "Hammerclaw was so great!"
- "[He] was a great warrior, and StarClan will honor him!"
- —DiamondClan cats honoring Hammerclaw at the gathering Hidden Prophecies, chapter 4
- "The river has three Crocodiles in it now, but we need the river to catch fish and drink water! Hammerclaw died trying to get a drink!"
- —Gaypaw explaining what happened to Hammerclaw Hidden Prophecies, chapter 4