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The Lost Series: Albegas: The Voltron that never was.
Most Voltron fanatics know there were, in fact, two Voltron's. Some are even familiar with the Japanese shows that spawned them. But not everyone knows that Voltron: Defender of the Universe came close to being a trilogy. WEP had considered adding a "Gladiator Voltron" to their line up. This Voltron's adventures would have been culled from Toei's 1983 series Luminous Flux-God Albegas. While it's not clear how it would have been worked into the Voltron mythos over here, Albegas' Japanese exploits went as follows: Professor Mizuki creates three giant robots to protect the Earth from the invading insect-like Dellinger aliens.
Called Alpha, Beta, and Gamma, they can unite into a variety of combination robots and vehicles, the most powerful being a huge, Gladiator-type warrior called Super Albegas. Alpha, Beta and Gamma are piloted by Daisakau Enjoji, Tetsuya Jin, Hotaru Mizuki, respectively.
The reasons why WEP scrapped this idea remain vague. Perhaps, with "Lion Voltron" already out performing it's Vehicle counterpart in the states, it was felt a third Voltron would be even less popular, or not needed at all. Strangely, though, some Albegas toys ended up in the Matchbox assortment, offering at least a glimpse of "the Voltron that never was"."