Amongst all the TF5 movie art showing up lately, some early Gen1 and pre-Gen1 drawing proposals have shown up on twitter (WARNING - a number of
their other tweets are for Adults only), similar to the unproduced ideas in the back of the original Generations book.
This one has ideas including a transforming toy carry case, a giant Optimus battlestation, and some early ideas for Metroplex.
While this one has what looks like could have been an Autobot Volcano/Ark base playset, and a very very big mobile battlestation (if the tiny Sideswipe car is to scale with it).
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