Formula 3x9v21

a..k.a. Prisms v21

SET UP

• Pencil and paper, OR

• A 9x9x9 prism grid board

• A set of 21 double sized sticks.

• A bundle of side sized sticks, (enough to completely fill the board).

• A bag of uniform stones for each player.

• The game starts on an open field.

• The Player to move first is randomly selected.

• Players take turns in a clockwise direction.

Number of Players

• 2 or more.

Objective

• Try to capitalize by following the last double sized stick placement for a potential mid game advantage.

• Ultimately, at the end of the game, to be the player with the most claimed territory.

Rules

• To start the game, players place a double sized stick anywhere on the board to complete 2 sides of 2 triangles.

• Once the 21 double sized sticks are played, the game continues with single sized sticks.

• On your turn, place a stick on any open adjacent side of a triangle on the grid, outside edges included.

• If your placement completes all 3 sides of a triangle, you claim the space with one of your pawns, and it is your turn again.

• Play continues with alternating turns until the board is completely filled.

• Claimed triangles are counted to determine who won with the most claimed territory.

• This game could end in a tie, depending on the number of players.

Player Variations

• Any number of players.

History

• Formula 3x9v21 , a.k.a. PRISMS v21 is a Rico original game designed in 2025, with special thanks to a most competitive counterpart and friend, Alison Rothwell-Mcadorey, for helping me work out the mechanics, dynamics, and the rules.

• Formula 3x9v21 can be found all over Rico’s game room. It can be found on the Abstract Avalanche, The Bar Arcade Collection, The Tidal Forces Collection, The Sticks and Stones Series, and the Head Games shelves.

• It is simply the old school classic ‘Dots & Boxes’, played on a 9x9x9 Prism pattern with an opening twist of sequence and deduction.

• The game of 21 is also a big influencer on this PRISMS variation.

Game Theory / Game Dynamics

• The simple beauty of this game is all it takes is pencil and paper. Draw points (dots) on the paper to indicate the corners of 60 degree triangles intersected to make a full sized 9x9x9 prism grid. When triangles are completed during game play (called prisms), you claim the space with your initials or a unique mark, like X’s and O’s.

• The new pattern introduces new mechanics, strategies, and a new dynamic to build your empire.

• The first 21 stick placements introduce a mid game opportunity, and a shift in strategy.

• The player whose turn that follows the last double sized stick placement usually has an advantage to capitalize on claiming several triangles.

• The 21 larger sticks played first introduce the dynamics of the game 21, in which you want to deduce the remaining number of large sticks left to play, and the sequence of players, ideally to follow the last larger stick placement.

• Filling the board with side sticks can take time, but at some point the options become scarce.

• The 21 larger sticks create emerging structures and pathways.

• Paths and maze patterns begin to form where if one prism is completed, it can open the opportunity to complete more.

• And OH! How satisfying it is when your opponent leaves you prisms to complete, which you take, and can place your final stick of the turn that provides nothing in return. (a placement you see, that they had missed!)

• And hence, this is where trash talking starts.

I hope you enjoy playing games,
as much as I have making them.