A popular patience game, although it hardly ever works out. Demon is also known as Canfield. It is played with a single pack of cards. Here are the rules (there are a large number of variants).

Deal a packet of 13 cards face up (called the stock) and deal a row of four cards face up next to it - you can pack on these cards. The object is to build the aces up in suit to the kings (variant: deal out one more card. This will be the base, and the object is to build all cards of this rank up in suit to the card one below them, with ace following king).

If possible, you can pack cards from the row of four on top of each other in descending sequence and alternating colour, moving whole sequences at once. When a gap appears in the row, it must immediately be filled with the top card of the stock. (Once the stock has run out, gaps can be left open or filled with any available card.)

When you've done all you can with the initial cards, deal the pack onto a wastepile three cards at a time. The top card of the wastepile is exposed, so you can pack or build it. When you've dealt through the pack, turn the wastepile over and start again. You can deal through the pack as many times as you like.

In the computer game "Canfield" for Unix systems, you are playing Demon for money. You must pay £52 to play a game, and you win £5 for each card you build (you also lose money for taking too much time or having the computer tell you about cards you've seen but can't see now.)