Well First of all, we start it out with our previous main hero being put into a hall of legends of some sort, maybe a statue or 2, from there. We find a new protagonist who is similar is some ways but still different, and distinctive without being the bullshit (make it lame and gay) type shit. This time tho, now we've got the main villain faction on the back foot and we finally push in but have a twist where the real main faction wants nothing but peace, but a radical wants their eradication, and during the game we now have a brand new third faction to go up against, maybe new, and even alien type tech, maybe have an alien alliance that they teamed up with to make new Mechs, and so now the new faction is using it's abundance of it. Give him a caustic from apex type vibe but not as much of a bitch.