AI

The exact inner mechanics of the AI remain a mystery. However, some general rules of its behavior are known. Those were either deducted through observation of the AI's movements, or they have been stated by the creator himself on the forums.

Weighted Random

The AI constructs a list of actions it could take on each turn, along with a value of how strongly it feels it should do that action. It then does a weighted random against that list. This means that the AI is never perfectly predictable, but it does have tendencies.

General behaviour of the AI

Confirmed:

• It currently does not know how to use any card other than the reinforcement card. ^{[1] [2]}
• It prefers to expand as long as it still sees neutral bonuses to expand to. ^[3]
• When deciding whether or not to complete a bonus, the AI currently uses (bonus value) * 3 - (armies we'd have to kill to take the bonus). If this comes out negative, it won't deem the bonus worthy in some cases. ^[4]

Observed:

• It tends to attack with twice as many armies as the territory is showing. ^[5]
• It generally only places armies in a few spots and attacks from them. ^[6]
• It tends to prefer neutral territories over player controlled territories, but it mostly prefers to attack the weakest territories. ^[7]
• It tends to favor getting bonuses and breaking enemy bonuses higher than making random other attacks. ^[8]
• It tends to issue attacks with all of its armies in a territory with more than one army and is unaware of the fact that one army must remain on every territory while attacking.

Behaviour of the AI in team games

• It will only attack teammates in two circumstances:

1. If a bonus is entirely controlled by teammates and it has >= 50% of the territories. It will only do attacks of 2 then.
2. If it's expanding into a new bonus that no teammates control. ^[9]

• The AI will not play cards when teamed with a human teammate unless it must play cards by rule. The only circumstance where an AI must play cards when teamed with a human teammate is if the last player on a team turns into an AI via boot or surrender and cards must be used by that team that turn.

Changes

The AI's behavior has not been changed since it was introduced in 2009. Changing the AI's behavior, even slightly, would invalidate every single-player score that's been achieved. If the AI is to be improved in the future, it will likely be done in conjunction with a revamp of the single player levels.

Playing Itself

Under the single-player tab, you can set up a game full of AIs, no fog and watch the entire game play out on its own.

However, under the multi-player tab, the AI will not play a game without any humans involved. If only AIs remain in a game, the AIs will simply vote to end. If voting to end is not possible, such as in a tournament game, the AIs will just pick a winner randomly. This restriction is necessary due to the way that multi-player games work. Due to WarLight's flexible engine, someone could construct a game that took thousands or millions of turns to finish. For example, a game with no bonuses or large wastelands separating players. The WarLight server would strain to complete these games, likely causing the entire site to grind to a halt.