Very good at simulating land warfare. There are a couple expansions that when combined together allow you to play 4v4 with a team leader directing one of three lieutenants who have control over each third of the board.
Computers are only just now starting to be able to beat humans at this. Used to treat senile dementia in Japan. Emperor of Tibet decided over a game. Nuking Hiroshima only caused a four hour delay of a title match. Complete, official Japanese records go back to the 1400s. The second largest wiki on the internet is devoted to this game.
There are really only 2-3 rules for placement. The game ends when one player resigns or when both players pass in succession. Scoring is simple.
2-6 players There are 6 playable groups and all are always used. The game is designed to be played with 6 players. 3 player games have everyone taking control of two factions, and the rules make allowances for asymmetric setups with 4 and 5 players. And there's a 2-player variant that changes the rules more drastically.
Full game playtime for 6 players is 8 hours (assuming everyone is familiar with the rules). The game was apparently play-tested over email and forums. The rules appear to be similar to Twilight Struggle or 1960: The Making of a President, but I can't confirm that.
The two books that comprise the rules are each about 40 pages.
2-6 players (with the expansions) hand management simultaneous action selection variable phase order
This was one of two games mocked up to be the card game version of Puerto Rico. One game became San Juan, the other became this. You can feel the similarities. Very light on player interaction, but you will spend more time thinking about what other players are doing than in Dominion.
Rules are printed on cards in a symbolic language described on a variety of cheat sheets. Most people know the game after a single play through, and it plays quickly.