Combat Mission: Beyond Overlord (CMBO), developed by Big Time Software and released by Battlefront in 2000, is still one of the best, if not the best tactical level computer war game available. Since its release, it has received only excellent reviews from all self-respecting magazines and web sites. It has also received dozens of awards.
According to the official web site, CMBO is a "1-2 player, turn-based, simultaneous-execution 3D simulation of WWII tactical warfare". The game is divided to two phases: orders phase and execution phase. During the orders phase, the game is paused and you can command your units in peace and quiet (except if the game has a time limit for the orders phase). After both players have confirmed their orders, the game calculates the turn's actions and the one minute turn is played back like a replay. This is the execution phase, during which you cannot give orders anymore. You can rewind and fast forward the replay as much as you want (normal VCR controls are available). After the execution phase comes the orders phase again, and so on, until the battle ends. You can play against the AI or against a human player on one computer (hot seat), play-by-email (PBEM) or by TCP/IP over the Internet.
The game is set on the Western Front, from Normandy 1944 to Germany 1945. CMBO doesn't have a campaign, which is a slight setback, but instead a few dozen separate scenarios and some operations, which are series of a few battles on a single big map. It also features a random battle generator and a scenario editor, with locations including farmland, town and rural forests. Another setback is the lack of bigger cities, as the towns in CMBO are quite small and structures have a maximum of 2 stories. The smallest unit you can command is an infantry squad / team or a vehicle, and the biggest battles involve battalions, although battles are normally fought between companies or smaller units.
You might think that the 3D graphics and (semi)real-time gameplay are just modern gimmicks, but they also enhance the gameplay. Because the whole game is 3D, bullet trajectories can be accurately calculated in 3D and terrain elevations are much easier to visualize. The real-time gameplay makes simultaneous assaults by multiple units much more realistic, and also prevents many lame tactics possible in turn-based tactical war games (read: Steel Panthers), including the "expending the enemy unit's shots, driving next to him and then slaughtering him." The camera controls are not the best possible, but tolerable.
CMBO's realism is on par with, if not better than Steel Panthers (the ex-king of tactical level war games) and much better than Close Combat (the ex-king of "realistic" real-time strategy games). Because of the 3D engine, terrain elevations play a much bigger role in CMBO, if only because they are much easier to visualize in 3D. Morale is also excellently simulated. Unit statistic are quite accurate, but CMBO lacks a proper encyclopaedia of units, which makes comparing units difficult, especially before battle when you are "bying" units. Also, there is no list of units available when the battle has started, the only way to access all of your units is to cycle through them one by one.
A real-time game, especially with separated orders and execution phases (when you can't give orders), wouldn't work without a good AI, and fortunately, the AI in CMBO is excellent. Although it tries to follow orders as well as it can, the units make decisions on their own based on the situation (and its morale). For example, if you order a light tank, eg. Sherman to defend a hill, and a superior tank, eg. Tiger comes into sight, the Sherman (wisely) flees and drives behind the hill to hide from the superior enemy unit. Also, unarmored trucks refuse to drive through heavy enemy fire. The units are not too independent, though (which is a good thing). For example, they don't assault without an order, although they will shoot at enemies which come too close even if they are ordered to hide. To put it simply: the units are people, not self-sacrificing robots.
To sum it up, CMBO is one of the best war games available, and a must-buy for all war game fans (although most war gamers already own this game). The sequel, Combat Mission: Barbarossa to Berlin is already being developed by Big Time Software, and is going to be set on the Eastern Front (including the Finnish Winter War).