The forgotten ones are massive and powerful tentacle-bearing aberrations living in the deepest reaches of Azjol-Nerub. Forgotten ones are eager to return to the world above. One appeared in a mission in Warcraft III: The Frozen Throne, where it was defeated by Arthas and Anub'arak as they journeyed through the lower reaches of Azjol-Nerub.
The forgotten ones lead the mysterious faceless ones. They can "spawn" armies of tentacles to aid.
In CataclysmThis section concerns content exclusive to Cataclysm.
In Warcraft III: The Frozen ThroneThis section concerns content exclusive to Warcraft III: The Frozen Throne.
In Warcraft III: The Frozen Throne, there was a chapter entitled The Forgotten Ones where Arthas and Anub'arak fought through an army of faceless ones and tentacles, with a massive Forgotten One as the boss at the end of the mission. The entire chapter being entitled The Forgotten Ones further points out that there were more than one of these creatures (or probably just refers to many of the Old God's servants as "forgotten"). Anub'arak points out that the forgotten one fought by Arthas was but one of the creatures, "a forgotten one".
Chris Metzen in BlizzCast 12 stated that Blizzard "had old gods in Northrend in Frozen Throne". During Patch 3.1.0 the old God was revealed to be Yogg-Saron (and not a forgotten one), whose entire body is trapped within the frozen roof of the world.
Forgotten ones can be placed on a map through the World Editor, accessed through the Unit Palette under the "Icecrown Glacier" set.
Forgotten ones are level 15 (attacking with Chaos), can summon tentacles, in addition to being capable of performing Firebolt and Charm. Forgotten ones are incapable of moving, as they are classified as a building under the World Editor.
- Anub'arak: It cannot be... A forgotten one! Look to your defenses, Death Knight! Fight as you've never fought before!
- The Forgotten Ones bear a resemblance to C'Thun.