The character played by actor Mackenzie Gray in director Zack Snyder's BC-filmed 'Superman' movie, is not 'Lex Luthor' or 'Brainiac', but another notoriously well-known DC Comics' super-villain :
Mackenzie Gray plays the character 'Jax--Ur' a rogue scientist, minion of 'General Zod' and the first super-villain to be projected into the prison 'Phantom Zone'.
'Jax-Ur' first appeared in DC's "Adventure Comics" #289 (1961) created by Otto Binder and George Papp.
An amoral and criminally deviant scientist on planet Krypton, Jax-Ur was imprisoned in the 'Phantom Zone' for destroying 'Wegthor', an inhabited moon of Krypton, while experimenting with a nuclear warhead-equipped rocket. His sentence for mass murder was imprisonment for eternity.
Jax-Ur was often plotting against Superman with fellow Phantom Zone inmates 'General Zod' and 'Faora'.
But after learning that Krypton was actually destroyed by a super-villain named 'Black Zero', Jax-Ur and the Man Of Steel become allies to prevent Black Zero from doing the same to the Earth.
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