|Release date||28 November 2005 (Update)|
|The master of all rats.|
It can only be fought by the player's kitten or cat. If the player asks their cat to be cautious, the cat will flee when half its hitpoints are left. If not, the cat will fight to its death. Players should be warned that if their cat dies, they have to get a new one from Gertrude.
- The king rat has 10 hitpoints and can only hit cats for 1 damage. However, it can hit fairly accurately, and the damage adds up. The cat may also have low hitpoints if it is not fully grown.
- Players can use raw or cooked fish on the hole in the wall to heal their cat. If the cat is still a kitten, it is recommended that players bring a full inventory of fish for the fight.
- The king rat is much stronger than any other rat a kitten can currently attack, so it is recommended that players equip their Catspeak amulet and tell their cat to fight cautiously, allowing it to run away if it loses more than half of its hitpoints.
- Overgrown cats CAN be used for this fight