Originated from Oh Hell! or "Up and Down the River" which are played with a standard deck of 52 cards. With a proprietary 60 card deck comprising a standard deck plus 4 Wizards (high) and 4 Jesters (low). In the first hand 1 card is dealt to each player. In the second 2 and so on. The game is over after the hand in which all cards are dealt.
Trumps are determined by randomly showing a card from the rest of undealt pack, if the card is a Jester, NoTrump is played in the current round. If it is a wizard, the last player to bid gets to choose the trump, or choose to play NoTrump.
After examining your cards you state the number of tricks you will win. Each round each player puts down one card. The first Wizard played wins the trick, followed by the highest trump card, followed by the highest card in the suit of the first card played.
You get 20 points for correctly predicting how many tricks you will win, plus 10 points for each trick won. You lose 10 points for each trick over or under the amount you predicted.
The game has plenty of luck inherent into it, especially at first (the first few rounds). Later rounds have very little luck, and because scoring increases over time (more cards are being dealt, so bids are higher), the overall game is a very skillful game.
Good memory, counting, and knowledge of statistics are helpful in this game.
[However, "Wizard is pure fun, challenging, baffling and simply habit forming. Wizard is quickly becoming the most popular card game of the decade," according to the undated box. So presumably everyone can enjoy it, skilled or not.]
This game can easily be played with a standard deck with some jesters and extra cards with the same backing, but has been sold in various formats over the years as a special deck with wizards and jesters added. It differs from the games it originates from in that the typical format was to start at one card dealt and go up to the maximum amount, and then go back down again (in some versions this ordering is reversed and you start dealing the maximum amount down to one card, then back up). Wizard shortens the game by starting at one card dealt and going up the maximum (which sometimes makes the last round have no trump since if the deck is divisible perfectly by the amount of players, there is no card to flip to determine trump in the last round).