Werewolf (Creeper) works with any Fluxx (ways to get rid of Creepers would be helpful, but this set includes the Seer and Angry Mob, both of which include that function). It has a Doom counter for extra compatibility with Cthulhu Fluxx. It says:
No one can win if you have this. During your turn, discard a Keeper or another Creeper in play. Move this to its owner. Discard this if no targets exist.
Seer (Keeper) works with any Fluxx. Shows an Investigator symbol for extra compatibility with Cthulhu Fluxx. It says:
If you have this on the table, once during your turn you may look at the cards in another player's hand, or you may discard this to discard a Werewolf. Counts as a Friend.
Angry Mob (Keeper) works with any Fluxx. It says:
If you have this on the table, during your turn you may move it to another player and discard one of that player's Keepers or Creepers.
Howl at the Moon (Goal) works with basic unthemed Fluxx (or Star Fluxx, since they it has a Moon as well) and also requires the Werewolf. It is redundant in Monster Fluxx. It says:
You win if you have the Werewolf and the Moon on the table in front of you.
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