Metal Bugs were a diminutive Metal Head subspecies, featured only in Daxter. They comprised the main enemies of the game, and were led by Metal Kaeden, who was under the control and direction of Metal Head leader Metal Kor. The Metal Bugs were the object of the initial plan to invade Haven City but ultimately failed due to the death of Kaeden by Daxter. This prompted Kor to invade Haven City himself, leading to the events of Jak II shortly afterward.
Similar to the Metal Heads, the Metal Bugs have no unifying creature form, but instead come in a vast variety of types and sizes. However, they do all have common traits, including insectoid heads, biomechanical bodies, and a skull gem.
Metal bugs were likely only instituted as an initial, experimental plan to invade Haven City, as it is unlikely they took part in the bigger Metal Head Wars and appeared to be reasonably separate from their parent race. Metal Kaeden's role and origins are unknown; whether or not he was the creator or leader of the race and his previous role within the Metal Head society was never revealed.
Metal bugs only made their presence known just before the events of Daxter, Osmo and Taryn calling them "new", further suggesting that they were merely experimental. Similar to metal heads, metal bugs also infested surrounding locations outside of Haven's walls, either as a means for scouting, residence, or sabotage outside of city limits. They did not make any appearances following the events of Daxter, and presumably went extinct after Kaeden's death.
In response to the various extermination companies present in Haven City, of which exterminated pests other than metal bugs, Kaeden disguised himself as a human inspector and began shutting down the companies to help aid the invasion. His means of shutting these companies down remain unknown, though he had told Osmo that if he did not complete more jobs than the company would be his. Osmo's company, Kridder Ridder, was the last standing company by the time of Daxter. This is the company that employed Daxter, who proved to be very effective in exterminating metal bugs. While Kaeden ultimately succeeded in destroying Kridder Ridder, he was subsequently killed by Daxter. As a result of Kaeden's failure, Kor disguised himself as a human to gain the trust of young Jak as well as the Underground, leading to the events of Jak II.
Similar to the Metal Heads, the Metal Bugs have a diverse physiology with many different sizes, capabilities, and appearances. However, they do possess defining traits, such as an insectoid head, organic skin beneath metallic if not mechanical armor, beady yellow eyes, and the presence of a skull gem.
Also similar to the Metal Heads is a lack of sapient intelligence. Aside from Kaeden, no metal bugs were known to speak, instead using various grunts, shrills, and growls to communicate or indicate their emotional state. In fact, many of the vocal sounds uttered by bugs sounded quite similar to a metal head (for example, metal backs sound identical to manic heads).
Metal bugs can adapt to any environment, and do not appear to have a natural habitat, aside from possibly the Metal Head nest from whence they may originate. They are seen infesting industrial, dirt-based, and flora-based environments, such as the construction site, strip mine, Breezy Valley, and others.
Metal bugs have a very odd reproductive system, and unlike metal heads do not come from the typical eggs. Spawners were perhaps the most usual examples, spawning either metal backs or flankers from their purple, bulbous shaped bodies. Drifters were capable of spawning metal bugs asexually, producing either metal backs or more rarely, metal creepers. Additionally, the hive queen at the strip mine had a detachable abdomen that served as an egg sac, capable of producing flankers, metal klaws, and termites. Similarly, the Altum sonatur queen spawned metal backs from her egg sac that had the appearance of a massive spawner.
|Drifter||Tanker, lumber mill||A nearly-invulnerable spawner, capable of producing metal backs and metal creepers. They are only able to be destroyed with an ultrasonic blast or with bug zappers.|
|Flanker||Construction site, strip mine, tanker||A wasp-like bug, closely resembling a metal jacket.|
|Metal back||Almost everywhere||Very common, weak, and small beetle-like metal bugs encountered nearly everywhere, evidently serving as the grunt force of the Metal Bugs.|
|Metal creeper||Brewery, transit system, tanker, distillery, construction site, lumber mill, prison||Fast bugs that spit poison and climb walls, but have little health.|
|Metal klaw||Transit system, distillery, construction site, lumber mill, Haven Palace, prison||Agile, sharp-toothed metal bugs that moves in a zig-zag pattern.|
|Metal slug||Construction site, strip mine, fish cannery, Haven Palace||Bugs that hide underground and spit dark eco from long range.|
|Slasher||Brewery, strip mine, tanker, fish cannery, Haven Palace||A large, powerful bug that has a comparatively large amount of health.|
|Altum sonatur queen||Transit system||A massive hive queen boss, encountered in the bottom regions of the transit system.|
|Strip mine hive queen||Strip mine||A large hive queen lured to a trap in the strip mine. Resembles a large wasp, with a detachable abdomen serving as an egg sac.|
|Breezy Valley hive queen||Breezy Valley||A large, winged hive queen, with no means of offense, similar to metal head scouts.|
|Emerald isle hive queen||Emerald Isle||Comparatively small, semi-aquatic queens, with blue frays around the perimeter of the body with which they achieve high-speed flight and swimming.|
|Spawner||Fish cannery, strip mine||A plant-like bug capable of spawning other bugs.|
Note that the images are not to scale.