The Omni-Enhanced forms are malfunctional hybrids[1][2] that could be acquired using the Upgraded Omnitrix. This feature was created after Upgrade was sacrificed to upgrade the Omnitrix in Omni-Tricked: Part 4 and was fixed after the Omnitrix rebooted in Innervasion Part 5: High Override.
Sometimes, when Ben transforms into an alien, he will be consumed by blue energy and rocks which will form the enhancements. These enhancements will either give the alien new powers or boost its pre-existing ones.
Some upgrades get rid of old powers, such as Stinkfly's goo and stinky gas or Grey Matter's small size.
Innervasion Part 4: Mind Over Alien Matter revealed that when Ben used Upgrade to enhance the Omnitrix, it rebooted and destroyed Upgrade's DNA, with a part of him fusing with Ben's DNA to survive, resulting in the creation of Glitch. Glitch then had to replace the missing alien DNA with another alien, being Shock Rock. However, Shock Rock's energy is so powerful that it messed up with the other aliens' DNA randomly, resulting in the Omni-Enhanced forms. When the Omnitrix rebooted itself at the end of season 2, it fixed the glitch that caused Omni-Enhancements in the first place and effectively removed them.
The enhancements for some of the aliens (namely Omni-Enhanced Heatblast's jetpack, Omni-Enhanced XLR8's energy wheels and Omni-Enhanced Overflow's cannons) were inspired in-universe by Fulmini weaponry.[3][4]
Omni-Enhanced forms are similar to Ultimate Forms, both being upgrades to the original aliens that can be undone.
For marketing purposes, Shock Rock is considered an honorary Omni-Enhanced alien.
