This version of Atomic Robo-kid is a Japanese release, differing from the Type-2 versions in unspecified ways.  Without further information, it's difficult to pinpoint what, if any, gameplay differences exist compared to other releases.  The game's origins and developer remain unconfirmed.  The absence of the 'Type-2' designation suggests a possible earlier or distinct release variation from the other versions.

Atomic Robo-kid (Japan)

Atomic Punk (US)