|Homeworld||Unknown location within Tetra Galaxy|
The Quadtroid is a species with a similar name and lifestyle, but that is wholly unrelated to the Metroids. The species appears in the Alimbic cluster in the Tetra galaxy. They are not natural entities, and were created by a sapient species - presumably the Alimbics. However, because of the name similarity, they were likely created with help of the Chozo. The Quadtroids were created from the genes of organisms most similar in overall design to leeches and reptiles. The creature is almost exactly the same as the Metroid; it even has the ability to suck the life out of victims, except that it crawls and has a tail. They also appear to lack the susceptibility to cold that Metroids have, as they have been spotted on the ice world of Arcterra.
It seems likely that Quadtroids have advanced setae on their feet, as they are capable of crawling across apparently any surface. Like Metroids, they feed on life energy and therefore seek that out specifically, attaching to a potential prey item and not letting go. Hunters and others with the technology at their disposal must remember to convert into their morph ball state and detonate morph ball bombs to dislodge the creature from them, or they will risk a quick demise.
Their original purpose is unknown, though the Alimbic may have created them to either serve a function similar to that of Metroids or as an attempt to fight off the dreaded Gorea. Whatever their initial purpose, they seem lost now, scattered around the Alimbic Cluster at the very least, hunting down food wherever they can.
- Metroid Prime: Hunters (First appearance)