This is a non-partnership precise-bid trick-taking game with a few twists.
The deck has five suits (1-King), with Mardi-Gras - related symbols: Masks, Crowns, Doubloon, Fleur de Lis, and Beads -- Masks are always trump. Plus there is one Mardi Gras card, which counts as the highest trump; and two FATuesday cards, which can always be played and count as the lowest cards (if led, a suit is declared). The 68 cards deal evenly with 4 players; with other numbers, leave out enough "1" cards so it goes evenly.
Each player bids the number of tricks he'll take -- the goal is to take exactly that many. If you make your bid you get 10 points per trick (a successful bid of 0 earns 10). If you go over, you get 1 point per trick taken; if under, you lose 10 points times your bid. Play until a pre-assigned total, such as 200 point.
The advanced Challenge game has extra rules: The Mardi Gras card can be declared when played as the highest or lowest trump; when led, each player must play their highest trump in hand. Bids are in secret, written down and revealed simultaneously. A Nil bid goes for 0 tricks and earns or loses 50 points. Finally, after the bids each player has a chance to double their own bid, to double the points at stake, except you also lose if you go over your bid.