Racing To The North Pole is a set of rules for a build-your-own card and board game. As the name implies, the game is about polar explorers in the early 1900s.
Justice League Unlimited Adventures is a build-you-own card game where players try to complete missions while opposed by villains.
Good Little Ninjas is a free print-and-play card drafting game. The author writes:
In Good Little Ninjas, players become inhabitants of medieval Japan. Each of the game’s seven rounds represent one day in the life of a bustling village, full of characters and opportunity.
Every day you have the chance to employ Farmers, Carpenters, Merchants and Peasants to harvest rice and construct buildings. The more daring might send Ninjas to raid the Palace Treasury, or recruit Samurai to prevent the predicted raids. You might even persuade one of the more powerful inhabitants to help you: the Daiymo, the Shogun, or even the Emperor himself!
Ultimately, the player who best uses their cunning to gain the most coins wins the game.
Good Little Martian is a print-and-play card game for two players. The cooperative game has one player stranded on Mars, and the other on a rescue mission.
Paranoia: Troubleshooters is a set of free rules for a card game based on the West End Games' Paranoia RPG.