Guns and Robots can best be described as World of Tanks meets Loadout. Let me explain why:
It uses the World of Tanks method of resolving objectives. If you blow up, that's it, you're out. If everyone on one side dies, the game is over. The objective rarely is considered in most matches because of this. It also uses the idea of disarming an opponent based on where you shoot. Shoot the feet, you slow the opponent. Shot the arms, you disarm it. Shoot the head, you impair it's vision.
It's like Loadout in that, in order to succeed, you have to experiment with your build. There are a sea of different parts, whcih are used to make modules, the components of your robot. Each robot is made up of one chassis, one engine, one body type, one battery (or two), one head unit, and 2 to 4 weopons and weapon frames. This means you can tailer the bot to match your strategy as much as you wish. To make this more absurd, you can equipt up to two devices, which allow you to pull the game to your advantage.
Also like loadout, you ave to buy every part. Unlike Loadout, however, there is a limited inventory for each part, and each part can only be used on one robot at a time, so you are encouraged to just have one, with a few spare pieces to mmix it up a few times.
In short, it's intense, it's annoying, but once you deal with it, it can be a really good game. Or a really bad one.