The barrier to burning Nintendo GameCube discs with a consumer DVD burner is the Burst Cutting Area, a "barcode" in the innermost ring of the disc, an area inaccessible to most burners and writeable only by very expensive disc pressing machines. For a long time the only way to run homebrew software on Nintendo GameCube was through a patching-system exploit of "Phantasy Star Online Episode I & II", requiring users to find the game and a Broadband Adapter. Both of these are difficult to find because a follow-up has been released (under the name "Phantasy Star Online Episode I & II Plus") and thus the original PSO was rarely sold after then, and because the Broadband Adapter was not often carried in stores due to the Nintendo GameCube's very limited selection of online games.