MW 4 is an old game - in fact it is ancient - no matter if you view it in human years or computer years, but it still compares well.
In the game you play Ian Dresari, the last known surviving member of the Dresari family, who rule a little planet called Kentares IV. The larger events going in the Battle Tech universe at the time of this game, namely the Fed-Com Civil War, have engulfed your tiny planet in a very personal way. The forces of Katrina Steiner have invaded your home planet and killed your family.
So your character, Ian Dresari, is out for Vengeance.
The game makes one major departure from previous incarnations of the game, and that is in the Mech Lab. You can customize your Mech in every way possible - paint scheme, engine, armor, optional equipment, and especially, what weapons it will carry. But with this last item, namely weapons, you are limited in a new way. Certain spaces on a Mech that are designed to hold a certain type of weapon, will only accept that type of weapon. A ballistic weapon space will only accept a ballistic weapon, an energy weapon space will only accept an energy weapon, and so on. Some mechs will have what are called Omni slots, which will accept any type of weapon, but of course you don't get these mechs until late in the game.
It adds an additional degree of realism to a game that is supposed to be a simulation.
Also the terrain and the general environment has much more of an effect on missions than in previous games. You can use terrain and/or time of day to make a stealthy approach to a target. In a major first, you can choose to play missions at night or in daylight.
The campaign game is progressive, in more than one sense. The missions are quite easy at the beginning of the game, allowing one to ease into the game and to actually enjoy it. However, the missions get steadily more difficult, even though it might not be obvious at first, because all of the missions are different in one way or another. By the end of the game the missions are hellaciously difficult.
You don't get access to the bigger mechs until the last operation of the campaign. This means that MW4 is not a standard shoot everything game but instead rewards good tactics.
And finally, your command responsibilities also progressively increase. At first you are responsible only for yourself. But by the end of the game you have three lance mates to command.
The Campaign is divided up into 6 chapters, each corresponding to a specific Operation, plus a climactic final battle. In each Operation there are anywhere from 3 to 5 individual missions to complete. The missions proceed on a linear basis, one at a time. It is only until the next to last mission in the game that you have a difficult choice to make.
Also one feature that gamers will appreciate is the ability to choose a difficulty level. You will have the same difficulty level throughout the whole campaign.
If you have not, in fact, ever played any of the Mechwarrior games before, fear not, there is an easy straightforward training session that will cover all the basics - steering a mech, controlling your throttle, torso twisting, weapons and heat management, and how to read the Heads Up Display. You can stomp around the grounds, blow stuff up, and generally learn how to pilot a mech. You will also get your feet wet quickly with your first Mech kill.
In addition to the Campaign and Training modes, there are two other modes - Instant Action and Online. Now it may be blasphemous to some that I have never played the game online, but I have warmed to the Instant Action area. During the campaign, you are limited to what weapons and mechs you get in salvage. But in the free play area you can play every mission in the game with any mech you want and any weapons loadout you can dream of. Seriously.
Having played both MW 2 and 3, MW4 compares favorably. In fact, this is probably my favorite version of the game, in terms of graphics quality, the realism of the game play, and the general context of the game. In short, I love it and can't get enough.
As I mentioned before, this game is ancient. It was released in 2001, I believe, when Windows XP had just come out. I discovered much to my very pleasant surprise that MW4 does indeed run on Windows 7.