- This article is about the race. For the monsters named simply Dagannoth, see Dagannoth (Waterbirth Island), Dagannoth (Lighthouse) or Dagannoth (POH).
Dagannoth are assigned by Chaeldar, Sumona, Duradel/Lapalok, Kuradal, and Morvran as Slayer tasks. The Balmung (as well as its upgraded form), released with the quest Blood Runs Deep, hits them very hard, similar to the effect of using Keris on Kalphites or Scabarites.
Little is known about the origins of the dagannoth species. Dagannoth are first documented in Third Age where they started attacking the Fremennik, causing great losses to them. The Fremennik people battle them to this day.
Through the Spirit Dagannoth they reveal their goal: To force the entire surface world to be plunged into the Deep through a terrible flood, the event is called "The Day of Rising" by the Dagannoths. The lucky ones will be consumed first by the Dagannoth while the others will drown before they are also consumed.
There are several types of Dagannoth, which vary by level, location and occasionally name. For information on a specific type of dagannoth, see its article.
- In the FunOrb game Armies of Gielinor, one may summon a Dagannoth, which uses the appearance of a Spirit dagannoth.
- Dagannoth may be based on the Deep Ones from H.P. Lovecraft's The Shadow Over Innsmouth. In the aforementioned story, they worshipped the elder beings Father Dagon and Mother Hydra.
- Dagannoth may also be based on the Xenomorph Aliens from the Alien movie series, as several references are made to them throughout the game.
- While the idea for the creatures characteristics may derive from the above mentioned, the name itself seems as if it may come from one of the first computer role-playing games, Dungeons of Daggorath, produced by DynaMicro in 1982.
- They may be dinosaurs; while fighting the Dagannoth Mother from Blood Runs Deep, a music track called "Maiasaura" unlocks, which is the name of a genus of dinosaur known especially for their maternal nature.