Illuminati: The Game of Conspiracy is a Card Game created by Steve Jackson Games (also known for their game Munchkin). In this game, there are secret societies trying to take control of the the world and its residents. The twist? You're one of those societies, and so are the other players. Every different organization has its own goal and powers, with the ultimate plan of being the only secret society left.
Illuminati: The Game of Conspiracy contains examples of:
Affectionate Parody: Of conspiracy theories (and, to a lesser extent, conspiracy theorists themselves).
Ancient Artifact: Several, including the Shroud of Turin and the Holy Grail. They provide special bonuses, and count towards the number of groups you need to win the game.
Flying Saucer: The picture for the UFO Conspiracy, for obvious reasons.
Greed: Crucial to the game- spending Megabucks can increase the power or resistance of any group, which can allow you to more easily capture or destroy a group, or defend another group from being captured or destroyed.
Lethal Joke Character: While it's true that the Church's powers put them at a major disadvantage in smaller games, in larger games- where you only need six or seven groups to win and people are constantly neutralizing and destroying each others' groups- they can easily dominate with a bit of patience.
The Man Behind the Man: The players become one ultimately, controlling a group which controls another group etc.
Milkman Conspiracy: while most groups you want are large and powerful, the small and jokey ones can still play a part in your strategy especially if you have a conspiracy that likes to collect things, like Discordia or the Assassins.
This specifically applies best to the Church of the SubGenius, which is an unintentional conspiracy of the mediocre and middle-class.
Mind Control: The Orbital Mind Control Laser, which can temporarily switch the types of a specific group.
For reference, the Assassins can win the game by neutralizing enough groups (it's implied that this is done through assassination), while the Cult of Cthulhu can win by destroying enough groups (which removes them from play for the rest of the game).