A design plan proposed by Japanese anime designer Yutaka Izubuchi, Godzilla vs. Berserk was submitted to Toho as a 14-page draft, one of the earliest concepts for what would eventually become Godzilla vs. Mechagodzilla II (1993).
As plans were being made to reintroduce Godzilla's mechanical doppelganger for the next Heisei "VS Series" film, the metal alien life form Berserk would have acted in the role. Starting off as a simple metallic organism, Berserk would have grown into a mess of wires and metal several times the size of a human, before eventually evolving into a Godzilla-sized replica of the nuclear monster. The plot also introduced the company collective of Teiyo, run by the son of the late Chairman Yasuaki Shindo from Godzilla vs. King Ghidorah (1991). A business of defense contractor, Teiyo would have been tasked with developing the Super-X3 in order to combat Godzilla and Berserk in its Mechagodzilla form.
Sadly, not much of what this unmade movie proposed would be incorporated into the final product, though the idea for a Super-X3 would eventually resurface for use in Godzilla vs. Destoroyah (1995).