The Temple guardian (also known as Cerberus, thus sharing the same name as the hellhound boss, Cerberus) is a dog-like monster that dwells in the entrance of the underground passageway to Canifis.
Players are required to kill the Temple guardian in the Priest in Peril quest. Magic or a cannon cannot be used to kill it. However, level 3 skilling pures can bring an inventory of saradomin brews and rings of recoil to slowly kill it without gaining combat xp, though at least 1 damage must be dealt by the player for the kill to count.
It is considered a dog in regards to Slayer tasks.
- If a player tries to attack the Temple Guardian after the quest Priest in Peril, the player will receive the message "I'd better not make the King mad at me again!". This refers to what happened during the aforementioned quest.
- Dark beasts used to look like a dark-brown version of the Temple Guardian.