Description

Tax is a 2-6 player card game using a deck containing four copies each of one through nine.

Deal five cards to each player and a sixth to the starting player. If playing with four, five or six players, deal a sixth card to the first and second players.
Place two cards face-up in the center of the table forming two separate discard piles.
On the side, place two cards face-up forming the communal card display.

Gameplay:
At the start of your turn, you must calculate the sum and the difference of the two cards atop the two discard piles.  At the end of your turn, you must be able to create one of those two values by performing one operation of addition, subtraction, multiplication or division between the two cards atop the discard piles at the end of your turn.

1. Play a single hand card to the top of one of the discard piles.
2. Play two hand cards, one to the top of each of the discard piles.
3. Play one hand card to the top of a discard pile and one communal card to the top of the other discard pile.  Communal cards are not replenished when used.  A player is limited to using one communal card per turn but may use both communal cards over the course of the round.
4. Fold and exit the round.  You can fold instead of performing one of the other actions.  If unable to perform one of the other actions, you must fold.

If the round has not ended, the next player in clockwise order who is still in the round takes his/her turn.

Round End:
If all other players have folded, the round ends immediately and the remaining player gains one point.

If a player plays his/her last card(s), the round ends immediately, and that player gains two points.

Collect the cards, shuffle, and perform the setup again.  First player rotates clockwise each round.

End condition:
The first player to reach or exceed a predetermined point value wins, for example 15 points.

Variant:
Want more information about your opponents' cards? At the start of a round after receiving their hand of cards, all players must place a single copy of their highest and lowest cards on the table in front of them for all players to see. These two cards are still considered to be hand cards. Players use these two cards just like their regular hand cards and they are folded when the rest of the hand is folded.

—description from the designer