Stealthbender

The Stealthbender is an Axon vehicle enhanced with Necris technology, that was supposed to be available in the Unreal Tournament 3 campaign mode after completing a certain mission.

"Right now, my favorite vehicle is the Stealthbender, which is a Hellbender hybrid that's been mutated by Necris technology. I really like that thing, because it deploys things like teleporters and all these different things on the map. Just in general, having a stealth-based vehicle is fun."

The vehicle's bigger part of the content was removed from the game before shipping and the only leftovers are some non-functional classes. The announcements such as "Stealthbender available" are still in the game though.

The StealthBender has been replaced in functionality (as described by Jeff Morris above) by the Necris Nightshade.