Malducci totally busted those screenshots wrong, so we can say that those screenshots aren't from the official arcade and x6800 versions that were released. However we also can't say they are from the allegedly unreleased Super Grafx version. Since we know that those shots aren't from the arcade or x68k version and the rumors of Super Grafx Strider are so popular, it could definitely be believable that they were from an unfinished Strider Super Grafx port
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By the way, handy grafx, what's with your harsh words on the PCE's 8-bit processor? True it's not official 16-bit, but it doesn't need to be because of how powerful it is
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