Colony: what holds for the layout and for play
None of the eight layouts of Colony favours the player who starts; they differ in the opening, draws and length. What holds for the jump and the copy, the endgame and simple rules against the AI.
Game: Colony
Colony has no chance in it, so what the setup does can be measured: the map, the start position and the empty cells give eight layouts. All the numbers come from games of AI opponents; people were not measured.[1]
Layouts
Normal AI against Normal AI, 800 games per row (empty cells off and on together):
| Map and start | First flip on move | First player wins | Draws | Moves |
|---|---|---|---|---|
| 58 cells, three pieces each | 3.7 | 48% | 4.4% | 115 |
| 58 cells, one piece each | 13.9 | 48% | 3.9% | 114 |
| 61 cells, three pieces each | 3.7 | 49% | 0.0% | 131 |
| 61 cells, one piece each | 13.8 | 47% | 0.0% | 132 |
- Neither the first move nor the side of the board decides in any layout: the player who starts wins 50.0% against the Weak AI, 48.0% against the Normal AI and 51.6% against the Strong AI (±1.7 points for the Weak and Normal AI, ±6.1 for the Strong AI).[2] The choice “who starts” is a matter of feel.
- With one piece each nothing is flipped for the first thirteen moves and there is hardly any jumping; after that it plays as with three pieces.
- The 61-cell map has no draws (an odd number of cells, the board is full at the end) and its games are longer: 15 to 20% pass 150 moves.
- The empty-cell rule ends 2 to 4% of the games of the Normal AI and changes the result in about one game in a hundred.
Copy and jump
- The board fills only with copies: a game has exactly 52, 56, 55 or 59 copies, depending on the layout, and ends with a copy into the last empty cell. Everything else is jumps.
- By a search to depth 5 a copy is better more often in the opening (42% of positions against 34%), a jump in the middle of the game (41 to 46% against 21 to 29%). When the search sees the end of the game in the endgame, the result is better after a jump in 60% of the positions and after a copy in 18%.[3]
Endgame
- The player who leads 40 moves before the end wins 51% of the games of the Normal AI, 12 moves before the end 69%, one move before the end 87%.
- The player who plays the last piece was behind before it in 86% of the games of the Normal AI and won only 27%; against the Strong AI 93% and 14%. Why was not investigated.
Against the AI
The rules are played by a script as a stand-in for a person; a real person would hold them with mistakes.
| Rule | Weak AI | Normal AI | Strong AI |
|---|---|---|---|
| the highest number of the hint | 54.5% | 0.0% | 0.0% |
| always copy | 45.8% | 0.5% | 0.0% |
| look at what the opponent takes back | 97.8% | 1.8% | 0.0% |
- A principle that was not measured: counting before the move what the opponent takes back beats the Weak AI; against the Normal AI one must also see one's own next move.[4]