From the Introduction:
Showdown at the Desert Fortress of Professor Anteater is a roleplaying game designed for 3 to 5 players. Showdown is a storytelling game in the vein of Fiasco or the Shab-Al-Hiri Roach. It differs from traditional roleplaying games in that there is no gamesmaster, instead the players are working together to create a great story. However Showdown also has a competitive element. The game is presented as a one-shot story, but players can replay as much as they want.
In Showdown each player creates a superhero who wishes to get a place in the Defenders of the Galaxy, the greatest superhero team on planet Earth. The heroes have been sent to defeat Professor Anteater before he can fire his Doom Laser. The heroes will have to work together to make it through the Professor's desert fortress, but at the same time they will be trying to show themselves to be the most impressive as only one of them will make it into the Defenders.