Puls is a game of mental arithmetic and timing. Each player is dealt 10 cards from the deck; cards are printed with numbers (2, 3, 4, 5, 6, 8, 9, 10, 12, and 15) in six different colors, with numbers and colors mixed. Also on each card is an arrow symbol. The objective: get rid of cards more quickly than your opponents.
Youngest player plays a card. The arrows on the card are now important; most cards designate two other players as legal players of the next card. That is, the card might have a branching arrow pointing left, meaning the player to the left of the player who just played this card, and the next player around the table to the left from him, are both valid players of the next card. Some arrows indicate only one legal player, and some indicate that all players, other than the one who just played a card, are legal.
To play a card legally, you must a) be one of the designated players, and play a card b) this is not either a factor or a product of the last card played, and c) also not of the same color as the card just played.
If you play a card illegally, you place it face down in front of you, and score 3 points. When any player is down to 3 cards, he may call "stop!", and at that point everyone scores 1 point for each card remaining in his or her hand. Low score wins, obviously. Repeat rounds until each player has dealt once.
The tension in the game is caused by the fact that winning means reacting quickly, but the penalty for error is severe. There is not a lot of strategy, clearly; you rarely have a choice of which card to play, and choices are what make for strategy. Victory goes to the player with quick reflexes and the ability to multiply and divide quickly in his head. But it's a fun game for a beer-and-pretzels setting -- and also, perhaps, useful as a form of arithmetical drill for primary school kids.