It is not 100% clear what the final Game Gear release was. Originally, it was indeed The Lost World, both in the US and globally. However, there is some uncertainty about Super Battletank. It was reviewed in magazines in 1994 but it's unclear if it was actually released at that time, or not until the release of the Majesco Game Gear in 2000, or possibly sometime in between. Majesco was doing Genesis reprints well before they were doing Genesis systems, so it's possible that even if only the Majesco version exists, it was released way before the Majesco Game Gear.