They were shared by an original developer.
A former Hudson Soft developer has published some never-before-seen documents for an abandoned Bonk game called Genjin Show ~Tobidase! VB Genjin~, which was under consideration for Nintendo's Virtual Boy device (as recently spotted by Gosokkyu).
Norihito Miyamoto (or @nori_bomber as they are known on Twitter) is a developer who started their career on the Sega MK III before working as a planner and producer on the Bomberman, Bonk (Genjin in Japan), Mario, and the Super Robo series. Recently on Twitter, after seeing a post about the Virtual Boy, they shared some images from a design doc for this cancelled Bonk game, giving a little more insight into what could have been.
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