Here's the fluff I wrote for my players if anyone is interested
Mecha are powerful
Conventional arms are neglibile to mecha. Generally, the only thing that can take down a mecha is another mecha. Generally.
Mecha can do almost anything
If you want to build your mech to have a power, you probably can. Teleportation, mind control, knock out gas, acid sprays, electronic jamming, cloaking, sandwich delivery system. Anything that isn't an I WIN button will probably be allowed.
Mecha can appear from anywhere
The hero speaks into a watchband on his wrist. A mecha appears. Storeage and where your robot hides when your not in it isn't really important. Don't get hung up on the details. Your robot can drop from space, hide in an underground volcano, tunnel under the ground, or grow from a cube in your pocket. Just think of something and go with it.
Mecha are special
Not everyone has one. If someone has one, they are probably important. Theres not a lot of infastructure set up for them, they aren't usually bought or sold, and you probably know, at least in passing, every mecha pilot out there.
Mecha can survive in any environment
Land, sea, air, space, the corona of a sun, the crushing depths of the deep ocean. Environmental hazards are not really a consideration.
Mecha have a special bond with there pilot
In this game, pilots are chosen by their mecha. They are synced together. Everyone starts at sync level 0. Increasing this sync gives potential rewards and consequences
Themes of the genre
Looking at some of the literature (i.e. cartoons), the mecha genre has a few themes
Freedom above all
The relationship between the pilot, those around him, and the giant robot,
War is bad
History
World War II was going badly for the allies. The German blitzkrieg has taken over most of Europe. The US has remained nuetral in the war, and is not showing signs of trying to enter the war. An American archeologist in the Nevada Badlands uncovers the frame of the mecha known today as Victorious. The team and the US military study the mecha for one week, until it suddenly powers up, engaged its rocket jets, and flew into the sky. The next day, the mecha is spotted in Brittan, fighting off bombers over London. Victorious was piloted by Micheal Burn, a pilot in the Brittish air force. Victorious leaves the U.K. shortly after. The Germans surrender in a week after Victorious and Micheal Burn have leveled the German war effort and armored divisions. Micheal Burn and Victorious become legends.
More mecha are uncovered as time gone on. Attempts to study them are foiled as after discovery they activate and seem to choose a random human as their pilot. Pilots seem attached to their mecha on a pychic metal. Attempts to separate a pilot from their mecha result in violent reactions on the part of the pilot and mecha. When a pilot dies, the mecha seems to choose another pilot at random.
The present day
It is Dec. 30th 2019. Nations are roughly in the same configuration that they are now. Mecha have seemed to act as a MAD deterrent, as much large nations have several mecha among there citizens. There are currently about 500 pilots in total. Mankind has reached Mars and started a colony there. Surprisingly, mecha have been found on Mars, and in a greater concentration than on Earth. Each major country on earth has a martain colony, exploiting the mineral wealth found there. Meanwhile on Earth, pilots fufill various functions, militarily, celebrity, mercenary, human wealthfare, science and more.
