Math Scrabble
TBD
| Designer(s): elara | Match Type: DM (for 2 players) |
| Featured in: The Choice is Yours | |
Strategy + Mathematics DM: Math Scrabble
In Math Scrabble, players use tiles to try and create valid expressions.
The game takes place on a 13x13 board. Players alternate turns placing tiles on this board to create an expression.
Setup and Drawing
Players are given 3 tiles of each number from 1-9 and 5 tiles of each operator (+, -, *, /). They must split these tiles into four bags (lettered A-D). A bag can contain any number of tiles of any kind. This will be done before the DM.
When a player needs to draw tiles, they may take any amount from any of the bags. For instance, if a player needs to draw 6 tiles, they may take 2 tiles from A, 1 tile from C, and 3 tiles from D. Afterwards, the draws will be randomly selected out of all tiles still in each bag.
Players may not take more tiles than there currently are in a bag. Drawing is private; in other words, the opponent does not know which bags you drew from.
At the beginning of the game, both players will draw 7 tiles in the manner described above. For the rest of the game, after a player plays some tiles, they will draw more until they have 7 tiles in their hand. (Near the end of the game, a player may not have 7 tiles in total, in which case they draw as many as they can.)
Expressions
Expressions in this game go from left to right or from top to bottom. An expression is a series of digits and operators, such that there are never two operators in a row, there is at least one operator, and the expression starts and ends with digits. For instance, here are some valid expressions:
1+6+4
2*5
3+42 (Concatenation is allowed. If a 4 tile and a 2 tile are adjacent, it is read as the two-digit number 42.)
19/51
Here are some invalid expressions:
12*+63 (the expression cannot have two operators in a row)
178 (the expression must contain an operator)
-14+4 (the expression cannot start with a -)
An expression is called point-earning if it is valid, and it evaluates to a number that is a power of 10 other than 1. For instance, 5+19*5 is point-earning. (Note that multiplication/division take precedence over addition/subtraction.)
Placing
When it is a player's turn to place, they must place some of their tiles to create a valid expression. For the first turn of the game, this expression must go through the star at the middle of the board (square G7). Afterwards, this expression must include at least one tile that has already been placed.
Players may only place tiles within one row or column, such that the tiles they place are all part of one expression.
It is allowed to place tiles in such a way that there is an invalid expression on the board. However, the "primary expression" formed must be valid.
For instance, in the following boardstate:
it is allowed to place tiles like so, even though there are invalid expressions on the board (5* and 5-). All tiles placed are in one column, and form a single valid expression (2*6-2).
Scoring
After a player has placed their tiles, their expressions are scored.
If an expression is point-earning, then the player earns 1 point for every operator in the expression, plus 3 extra points if the expression contains at least six new tiles from the current turn. In the above example, the player would earn 2 points, because there are two operators. But they would not satisfy the 3-point requirement because there are only four new tiles in the expression.
If a player creates multiple valid expressions in one turn, the expressions created are evaluated individually.
Passing
Players may also choose to pass. If they decide to do this, they are unable to place any tiles for the turn. Instead, they may choose any of the tiles in their hand to discard; they will draw that many tiles afterwards. (Or, as many as they can, if they cannot draw that much.)
Endgame
The game ends in either of the following scenarios:
- A player has no tiles in their hand (and none in their bags), and it is their turn.
- Both players pass for three turns each in a row.
Afterwards, the player with more points wins. If it is a tie, the winner is the player who reached that score first. (In the unlikely case of a 0-0 tie, the player with the Advantage wins.)
Timing
Players have 90 seconds for each move (combining playing and deciding what to draw), as well as 5 minutes of reserve time total. If a player runs out of reserve time, they immediately lose the DM.
Advantage
The player with the Advantage decides who goes first.
In addition, they have access to the Mulligan ability. On one turn, after drawing tiles, they may put those drawn tiles back into their bags and draw again, from the same bags. This ability can only be used once and its usage will be announced.
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Clarification: You may use notes. You may not use a calculator. (Obviously, this is on the honor system. Please follow it though.)
Clarification: Discards are public.
Clarification: When placing tiles, the "primary expression" created must include a tile that is already on the board.
For instance, if the current board is
.....
.....
.2+2.
.....
The following move is not allowed:
1....
+....
12+2.
1....