The cursed cards are a set of new, alternate character cards for Yomi. Yomi is a card game that simulates a fighting game. It tests your ability to predict how your opponents will act and your ability to judge the relative value of cards from one situation to the next.
You can use these cursed cards as a handicap to play against weaker or beginner players, or you can play cursed vs. cursed characters for a kind of hilarious lower-powered game.
The cursed characters all have a different epithet, too.
Grave, Wind Warrior -> Rusty Warrior.
Jaina, Phoenix Archer -> Phoenix Arsonist
Midori, Mentor Dragon -> Scrub Dragon
Setsuki, Ninja Student -> Outfoxed Ninja
Rook, Stone Golem -> Tiny Golem
DeGrey, Ghostly Diplomat -> Debaucherous Diplomat
Valerie, Manic Painter -> Depressed Painter
Geiger, Precise Watchmaker -> Careless Watchmaker
Lum, Gambling Panda -> Unlucky Panda
Argagarg, Water Shaman -> Savage Shaman