Chain Reaction

From Looney Pyramid Games Wiki

Under development

This game is currently under development, in the Playtesting stage. Feedback is strongly encouraged! Feel free to give comments on game design or structure on the talk page.

Chain Reaction
Designed by Richard Morris
Fire 'particles' at 'atoms' and direct the chain reaction to let you capture pieces
:Players Players: 2 - 6
:Time Length: Long
:Complexity Complexity: Low
Trios per color: 5
Number of colors: 6
Pyramid trios:
Monochr. stashes: 6
Five-color sets:
- - - - - - Other equipment - - - - - -
Volcano board
Setup time: 5 minutes
Playing time: 60 minutes - 90 minutes
Strategy depth: Medium
Random chance: None
Game mechanics: placement, stacking
Theme: Science
BGG Link:
Status: Playtesting (v1.0), Year released: 2011

Chain Reaction[edit | edit source]

Chain reaction is a Looney Pyramids game designed by Richard Morris. Whilst the mechanics are very different, it shares pieces with the classic game Volcano, and has a similar feel.

Components required[edit | edit source]

6 differently coloured Looney Pyramid Stashes - ideally all transparent colours.

A 5x5 volcano board (or chess board or any other appropriate object with 5x5 squares big enough to hold Looney Pyramids. In these rules a volcano board will be assumed). Where squares on the board are referenced in these rules, a (row, column) naming convention is used. Thus, for example, (1,1) is the top left square, (1,5) the top right, (3,3) the square in the middle, and (5,1) the bottom left square.

4 objects used to identify ‘black hole’ squares. If a Looney volcano board is used, their “little black squares” were, by definition, made for this purpose. Otherwise pieces of paper, coins, Zendo stones or similar objects may be used.

Number of players: 2-6

Playing time: 60-90 minutes

Overview[edit | edit source]

Chain reaction is a game played on a 5x5 board that represents a cluster of atoms. Each player in turn fires a particle into one of the cluster of atoms. If the conditions are right, this will cause that atom to decay and eject particles into adjacent atoms, which may cause a chain reaction if those adjacent atoms also decay. When the chain reaction has died down, the player collects any particles that remain on ‘black hole’ positions within the cluster of atoms. The winner is the player with the highest scoring collection of particles.

Setup[edit | edit source]

Place a single ‘black hole’ marker on the central square of the 5x5 board.

The game may be played starting with an empty board, but the first many moves will be mechanical and uninteresting while the players wait for the atoms to grow big enough to be able to decay and eject particles towards the centre of the board. So it is recommended that you start with the board seeded with pyramids, but in a manner where nothing may be captured by the black hole square in the opening moves. A suggested seeding which uses 2 trees of 3 pyramids of each of the 6 stashes (i.e. 36 pyramids), is as follows:

Suggested Starting Setup for 5x5
3 2 1 2 3
2 4 6 4 2
1 6 B 6 1
2 4 6 4 2
3 2 1 2 3

where 'B' is a black hole and the numbers represent the pip count of the pyramids on the square. In this set-up, a pip count of 1 comes from a single small pyramid, 2 from a single medium pyramid, and 3 from a single large pyramid. A pip count of 4 is a large and a small pyramid and 6 is a tree of a large, medium and small pyramid. Squares with more than one starting pyramid may either be of a single colour or mixed colours, as the players see fit. As you become more experienced with the game, you may wish to try alternative starting setups.

The remaining 18 trees of pyramids are the particles that the players will fire into the cluster of atoms, with each pyramid representing a single particle. Since the game ends when all particles have been fired, the game will consist of 54 turns. Share the 18 trees out equally amongst the players (9 trees each for 2 players, 6 trees each for 3 players, 4 trees each for 4 players, 3 trees each for 5 or 6 players). Players should get complete single-colour trees, with each tree being of a different colour. If any trees are left over, put the pyramids from them in a central pool of pyramids.

Players should set up their pyramids so that there is a clear distinction between the pool of pyramids used to fire into the atoms, and the pyramids that have been captured by that player.

Game play[edit | edit source]

Firing a particle[edit | edit source]

Each stack of pieces within the 5x5 grid represents 'extra' particles that may be ejected from an atom.

On your turn, you must select and fire a single particle into the cluster of atoms, exciting a single atom. If there are any pyramids in the central pool, you must chose and use one of them before you are allowed to use your personal supply of particles. To fire the particle, you should place it on top of the stack of zero or more pyramids on any square on the edge of the board. You may not fire particles into the middle of the board.

Determine if the atom that was excited by the fired particle decays, and if it does, eject particles from it into adjoining squares, exciting those atoms. Repeat this for all atoms that are excited by ejected particles in the chain reaction. You may choose the sequence in which the excited atoms are resolved, but must resolve each fully before resolving the next. Continue until the chain reaction exhausts itself with atoms all below the level at which they will eject particles. The other players are encouraged to point out atoms that are still excited enough to eject particles.

If, when the chain reaction has exhausted itself, there are any particles on black hole squares you should pick these up and add them to your collection of captured particles.

Atomic decay[edit | edit source]

An atom will decay when it is sufficiently excited by extra particles. The threshold at which an atom decays depends on the total size (but not the number) of the extra particles, and the positioning of the atom in the cluster. The size of each particle is determined by its pip count – one for a small pyramid, two for a medium pyramid and three for a large pyramid. The threshold for decay for an atom is extra particles with a pip count double the number of squares it is orthogonally adjacent to. Thus an atom in a corner square is stable when it has a pip count of up to three, but decays when its pip count is four or more. An atom that is on a board edge (but not a corner) will decay when it has a pip count of six or more. An internal atom will decay when it has a pip count of eight or more.

Black hole spaces have a different decay mechanism driven just by the number of particles on it. A black hole can only permanently hold a single particle. Any black hole square (wherever it is placed on the board) with two or more particles of any size must decay.

Particle ejection[edit | edit source]

When an atom decays, all the extra particles in that atom are ejected into orthogonally adjacent atoms (so the square for the atom becomes, perhaps temporarily, empty). Particles are always ejected in stack order, top down. You select the adjacent square that the topmost particle ejects into and then, by a quirk of quantum mechanics, each successive particle always ejects into the next orthogonally adjacent square in a clockwise direction. If there were more than 4 extra particles in the decaying atom, adjacent atoms may receive more than one extra particle, with the fifth ejected particle going to the same atom as the first ejected particle, and so on.

The 5x5 board is actually a two-dimensional representation of a three-dimensional cluster of atoms which is close to spherical. In consequence, for particle ejection purposes only, atoms positioned on the edge of the board are adjacent to atoms on the same row or column on the other side of the board. Thus, for example, if an atom on (1,1) ejects 4 particles, they will go to the squares (5,1), (1,2), (2,1), (1,5). Similarly, an atom on (3,1) will eject to (2,1), (3,2), (4,1) and (3,5).

Adding additional black hole squares[edit | edit source]

You may rearrange your captured particles whenever you wish, but you must form single coloured trees if you can, and may not beak them down once formed. Single coloured trees are worth more points than multi-coloured trees at the end of the game, but also trigger the placement of additional black hole squares. The player who forms the first single coloured tree must place an additional black hole marker on any empty square on the board that does not already have a black hole marker. Similarly, additional black hole markers should be placed when the sixth and eleventh single coloured trees are formed, allowing for a maximum of 4 black holes on the board.

Scoring[edit | edit source]

You should arrange the rest of your captured particles into as many mixed-colour trees as possible, since they are worth more than individual particles. At the end of the game, each player adds up his score as follows:

7 points for each single-colour tree

5 points for each mixed-colour tree

1 point each for any pyramids not in a tree

Ending the game[edit | edit source]

The game ends when all the particles have been fired into the cluster of atoms. The winner is the player with the highest score of captured particles.

Variants and optional rules[edit | edit source]

Restacking particles[edit | edit source]

If played with transparent stashes, the composition of particles on a square should be apparent, even if larger pyramids are placed on top of smaller ones, thus partially hiding them. If a player is unclear what the composition of a stack of pyramids in a square is, they may always carefully pick up and replace part of the stack.

However, if you prefer the clarity of never having a larger pyramid placed over a smaller one, you may play with the optional ‘restacking’ rule. When this rule is in play, every time a pyramid that is larger than the top piece of a stack is placed on top of the stack, the stack is restacked in size order with the biggest pyramids at the bottom of the stack. The newly placed pyramid becomes the topmost pyramid of its size.

Chain reaction on a 6x6 board[edit | edit source]

The game may also be played on a 6x6 board. This requires 8 differently coloured stashes. Start the game with two black hole squares (for example on (3,3) and (4,4)). The suggested starting set up is:

Suggested Starting Setup for 6x6
2 1 1 2
5 6 6 5
1 6 B X 6 1
1 6 X B 6 1
5 6 6 5
2 1 1 2

Where 5 is a large and a medium pyramid, X is two large pyramids, empty cells have no pyramids and the other numbers are as above.

With 72 pyramids to fire as particles, the game will be a little longer than on a 5x5 board, and may be able to accommodate more players. Two extra ‘black hole’ markers will be needed, with an extra black hole marker being placed when the sixteenth single-colour tree is made. All other rules remain the same.

Credits[edit | edit source]

Designed by Richard Morris

Playtesting and other assistance: will follow

Rules written by Richard Morris