In a Nutshell:
Mechwarrior IV is a tactical-level mecha combat game. You control your mechs on a variety of missions, in several different terrains. The game typically occurs at the level of lance vs. lance (groups of 4 mechs per side) battles, but larger melees do occur.
The game is more than just a shooter. You get to decide on what mech to use, and what equipment to put on your mech. This lets you decide, based on the mission requirements, exactly what is appropriate for your needs. During a mission, you also get to command your lance mates. These factors combine to make Mechwarrior IV a riveting game where your decisions, as well as your fighting ability, dictate the course of a campaign.
Play Modes:
Mechwarrior IV has several modes of play. First, there is the excellent campaign mode, which follows your quest for revenge over seven campaigns, in a variety of climates and conditions. Second, there are the Instant Action modes, where you choose a mission, mechs, equipment loads and proceed straight into the fighting. Finally, theres the multiplayer mode, which allows you and a bunch of friends to face each other in battle over a LAN or the Internet.
The Multiplayer Mode consists of the usual bit of team battles, capture the flag, last man standing, and so on. One nice touch is that one play mode counts damage inflicted, not kills, for scoreso you dont have to worry quite so much about people swooping in to kill off the person you worked to damage.
The Instant Action modes are similar to the multiplayer mode, though naturally its just you vs. the computer. A pleasant surprise is that you can play any of the campaign missions you have already completedwhich gives you an opportunity to try out what if I did this theories that you might have.
However, the Campaign Mode is one of the most engaging I have seen for an action game in a long time. During the campaign, you play through a batch of sequential missions. You carryover the same people, mechs, and equipment from mission to mission, in your quest to recapture Kentares IV.
Whats interesting, though, is that you are fighting a guerrilla war. Early missions have you performing hit-and-fade style attacks, sabotaging communications relays, and so on. Most importantly, you cant simply purchase equipment. If you want a weapon, youll have to find someone with itand take it. This adds a complex resource management aspect to the game. In order to get new mech bodies, you have to go out and capture/disable enemy mechs. Likewise, if you want a new PPC to strap onto your favorite mech, you have to make sure that you capture one intact.
During some missions, youll have to decide whether to go for a quick-but-dirty kill, which will lower the amount of equipment you can salvage from a mech, or try to kill with a minimum of damage. For example, some mechs have most of their weapons in an arm. If you blow the arm off, the mech should be an easy target. But if you do so, you wont be able to acquire the weapons in the arm for later use. On the other hand, if you dont take out the arm, those weapons will be used against you RIGHT NOW...
This adds an interesting resource management aspect to the game, without bogging it down in needless complexity. You just move and fight. The computer tallies up whats left over for you to salvage after the battle is over. If you want to play differently so you can acquire more stuff, you can. But you dont have to.