Syvalion (World, prototype) is a prototype version of Syvalion, released internationally. The term 'prototype' indicates that this version is an early, unfinished version of the game. It's likely to have differences from the final Japanese and international releases. The 'World' qualifier indicates a wider, possibly global, release compared to the Japanese version. Further information on differences from other versions and the development team would provide more insight.

Syvalion (World, prototype)

Syougi No Tatsujin - Master of Shougi