Battle Kid: Fortress of Peril, the new NES platformer (!) by Sivak Games, was officially released on an honest-to-goodness NES cartridge yesterday. The game, inspired by super-hard games like I Wanna Be the Guy, contains over 550 rooms and 8 bosses, and comes on a translucent green cartridge that is designed to work in any region's NES.

Unfortunately, only a day after its release, the game is "temporarily unavailable" on the RetroUSB site. It's not only difficult, it's now difficult to find! We're contacting RetroUSB to find out if a second printing is planned.

Update: RetroZone tells us that the item will be available again tonight around 7PM EST, but "supplies may be limited." If you want this, keep an eye on the site!

[Thanks, Levi!]

This article was originally published on Joystiq.

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