The Gerubus has only been observed as X Parasite-hosts or mimics aboard the Biologic Space Laboratories research station. Therefore, it is unknown if the Gerubus exists naturally, or if it is created by the X Parasites' ability to manipulate their hosts' DNA to make them more dangerous (such as Gold Scisers and Aqua Zebesians).
The Gerubus is larger in size than the natural Geruta, and its pincer arms also appear to have gained enormous metallic armor. This makes the Gerubus much more durable and able to resist Beam weapons, although it can still be killed with Missiles. Unlike normal X-infected Gerutas, the Gerubus behaves nearly identically to its natural counterpart: hanging on the ceiling and swooping down when Samus Aran approaches.
Interestingly, this variant is most common in Sector 5 (ARC), which is a sub-zero area. It does not appear at all in Sector 3 (PYR), the super-heated area that is more akin to the Geruta's native habitat in Norfair (and is home to many X-infected Gerutas in Fusion).
Several Gerubus also appear in Sector 1 (SRX), in the area resembling Tourian. In one instance, the X released from a defeated Yard will transform into a Gerubus, which will then become a Gold Space Pirate when the Gerubus is defeated; this sequence is necessary to open a Special Hatch and access a Power Bomb Tank.
- Metroid Prime and Metroid Fusion: Prima's Official Strategy Guide erroneously refers to a Gerubus as a Dessgeega at one point, despite otherwise correctly identifying the Gerubus by name.
- ^ Metroid Prime and Metroid Fusion: Prima's Official Strategy Guide pg. 137
- ^ Nintendo Official Guide Book for Metroid Fusion pg. 27, which has also been romanized as Geruboss by Metroid Database
- ^ Metroid Prime and Metroid Fusion: Prima's Official Strategy Guide pg. 112