Necronautica (2011)

From Introduction:

Necronautica is a short role playing game of brave heroes and heroines who have taken up arms against unfathomable alien forces from beyond space and time that threaten the human race and, indeed, the very fabric of reality itself. It is also my first attempt at a 24-Hour RPG since the Summer of 2004 – that is, Necronautica was designed, written, and laid out in 24 hours (so expect a few mistakes).

Necronautica assumes a basic familiarity with role playing games and how they are traditionally played. In the future, when I have more than 24 hours to do so, these things may be elaborated on in order to aid the hobby newcomer. For the time being, however, such things are deemed more a convenience than a necessity and, so, are being set aside in the interest of focusing on other aspects of the game.

This RPG is available as a free download from the designer's site.