Imagine the game with giant customizable robots fighting in a Real Time Strategy environment with your standard base building and battles going underground, on surface and in the orbit at the same time. Say hi to Metal Fatigue. Game was released in a year 2000 and it is a game that almost everyone missed, they missed the game that is one of my favorite RTS games ever made.
Story goes as three factions Rimtech, Milagro and Neuropa traveled deep into space to find the remains of ancient alien civilization only to discover that they are gone forever and and only thing left is to salvage the alien technology. Every corporation wanted the tech for themselves and that is how conflict between the factions was born. Real Time Strategy is where this game shines. Pick a faction, well rounded Rimtech, Berserkers like Milagro and Stealthy Neuropa offer nice contrast among factions.
Rimtech
Milagro
Neuropa
You can build a base and collect Mass for your production of normal vehicles and this game's most fun feature - Combots. Giant robots that you can customize to your will. Make a Combot with a shield and sword and make it very durable, or create a combot with sniper arms and flight torso to annoy your enemies, or create full on missile torso, missile legs and rail gun arms. Combinations for combots are endless and they are really fun to see in action.
Combots get stronger as their pilots level up and if your combots get destroyed you can save the pilots and use them on a different combot. You can salavage enemy combots parts and make combot combinations of every faction and create some really fun combinations.