The Little Battlers W introduces new Super LBX machines, which are created by combining thee others together. Sigma Orbis (above), for instance, is formed by combining Perseus, Elysion, and Minerva.
Killer Droid, on the other hand, is a giant enemy LBX that you’ll have to take on at some point. Level 5 released screenshots of both today. First up is the Sigma Orbis:
And this is the Killer Droid:
The Little Battlers W is in development for the PSP.