Ghostfreak (B10LT)

History:
Ghostfreak was rarely used by Ben because when he was used Ben did horribly violent actions that made him fear Ghostfreak.

Eventually this was revealed to be Zs'Skayr who escaped from the Omnitrix and and tried to take over Ben's body for the device to access his full form, this failed but he got his hands on a the Forever Knight's copied Omnitrix and used that to return to his normal state after possessing the body of a news reporter.

He died in a massive battle but was brought back to face Ben and the Plumbers by a team made up of Null Void convicts.

Over time he would meet the group on a few more occasions before being scanned by the Omnitrix, his soul would die but his form would be accessible by Ben from that point onward.

Design:
Indentical to the original Ghostfreak he gains a green eye by Volume 5 by having all his dark side erased.

Behind the Scenes:
To the writers they had a strong feel of what they wanted to do with Ghostfreak and Zs'Skayr, unfortunately this fell apart later on post Volume 2 so they just decided to give him back to Ben.