The Acmatrix is an Omnitrix created by Akyno, Azmuth's assistant, to replace Ben Tennyson's current Omnitrix after it's inevitable destruction. It contains DNA samples from the Milky Way, the Andromeda Galaxy, and the Triangulum Galaxy. It is the main Omnitrix in The Guardians.
The Acmatrix has a major glitch, being that it is unable to distinguish between living and nonliving organisms, therefore making it able to latch on to just about anything, even trees. After Akyno left, there was a foul-up causing it to attach itself to a damaged energy core. The excess energy from said core causes it to transform itself on multiple occasions, and with no conscious to drive it the aliens act on pure instinct. Typically when transformed, it tries to do one of two things: defend the space station from intruders, or escape the station itself. This causes many problems from episode to episode.