Megiddo

Megiddo is 1985 game by Steve Baldwin, associated with several different publishers.

The board is made of six concentric rings under a central six-point start. There are 36 pieces of three different colors (the third color is for the three-player version):

• Each player, on her turn, drops a friendly piece on an empty circle.
• Captures are custodian: if a piece is dropped, and there are two enemy pieces and then a friendly piece, all in the same direction, then the two enemy pieces are captured, and replaced by two friendly pieces.
• The allowed directions are (a) in the same circle, (b) in the same line, (c) making a spiral on concentric circles (cf. next example)

• Captures can occur in multiple directions at the same time
• Also, captures create a chain reaction: the new pieces that replace the captured ones might produce new captures, and so on. But notice that first all multiple captures must be executed before considering chain reactions.
  
• Pieces are always captured in pairs.
  
• Wins the player that either (a) captures six enemy stones, or (b) makes one of the three winning six-piece patterns, named radial, circular, and spiral:

The rules propose a multi-match game until one player reaches 36 points:

• Winning with a winning pattern: 6 points
• Any extra winning pattern: 12 points
• Each captured piece: 1 point
  

The rules also mention a 'Cleopatra' variation: the typical custodian capture does not apply if a player drops a piece between two enemy pieces, rule which the game follows. In Cleopatra, dropping a piece inside will capture the pieces on the extremes:

Here are some tips from the original rules:

The game is a variant of Pente (which itself is an iteration of Gomoku-ninuki). The fact that there are three very different types of direction (radial, circular and spiral) removes clarity to the game. Unless players are attentive, they will miss captures and even winning patterns.

Unlike Pente, it is easy to start using pieces at the edge, which have the advantage of being harder to capture. I'm not sure if this is good or bad, but it is an important feature in this game. The tips mention 'taboo points', places where a player has a winning threat if the adversary plays there, which is something common in the moku family. Matches will converge into a cold phase, where the first player forced to play in one of those points, immediately loses the game.

A review on GAMES #67: