日本国内でロストワールドになる前に存在したってロケテ版なのかな？

New working clones
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Forgotten Worlds (Japan) [Irongiant, Dumping Union]
Ryu Jin (Japan, ET910000B PCB) [Battlesmurf]

* Extremely early / rare version of Forgotten Worlds for the Japanese market, before the name change to Lost Worlds. Serial number indicates it's #22!