Why Did They Even Bother
This version does not contain a lot of what the console and PC versions had to offer. It did not feature the Matoran Enclave to purchase upgrades or extras. It also did not contain Piraka Playground, where the Piraka you have defeated hang out after you beat them. It's a real cut-down from the other versions of the game.
If you want to buy this game, but you don't know what to buy it for, anything but the Gameboy version. It's a waste of money even to rent it. Although, I would recommend the PC version, because (depending on how powerful your computer is) the graphics and CPU speed make it better than the console versions.