Revenant cyclopes are the undead versions of cyclopes slain in the God Wars. They are more dangerous than their combat level suggests, more than a player with the same combat level. They still can deal a significant amount of damage in combat with melee, ranged, and magic, up to around 200. Finally, like all other Revenants, it can also restore lifepoints rapidly and cure itself from poison a limited number of times.
Historically, these monsters, along with all other revenants, could freeze you from movement and block you from teleporting, but after the update on 1 February 2011 that relocated them to the Forinthry Dungeon, they no longer can do either of these.
WARNING: The Forinthry Dungeon is a PVP-enabled area, meaning it is entirely possible for other players to attack you whilst fighting the revenants in the dungeon. Do not bring equipment that you are not willing to lose.
Revenant cyclops were given a different set of sounds for being attacked and death to a player with the release of the Evolution of Combat. The only other revenants that were affected by this were the Revenant icefiend and Revenant pyrefiend.