Reddit reviews Mechwarrior: The Battletech Role-Playing Game (2nd Edition)

• Unknown Armies, where your obsessions affect reality
  
• Cryptworld and Stories from the Grave for 80s horror movie goodness
  
• Rolemaster Classic (Rules, Combat companion), for unpredictable combat
  
• Mechwarrior 2nd edition, which was super simple to play and run and has a crazy futuristic humans-only setting from Battletech
  
  EDIT: HARP from the makers of Rolemaster is also great, and much easier to start playing

If you want to play it I would strongly recommend you try the older (out of print, but available online) Mechwarrior 2e RPG over any other version.

https://www.amazon.com/Mechwarrior-Battletech-Role-Playing-Game-2nd/dp/1555601294

None of them are the greatest systems, but the 2e Mechwarrior rules match up most cleanly with the tabletop minis game, and really if you aren't playing that why play as Mechwarriors?

Uh, no its not. I have a half dozen MECHWARRIOR books, same with Battletech. Even the second edition of the Tabletop, was called Mechwarrior.

Went Battletech -> Mechwarrior -> Mechwarrior: Dark Ages -> Battletech again

Then looking at Wikipedia, they swapped the Bookline back to Battletech (BT -> BT: Dark Ages). Circa 2009. Some of us grew up on Mechwarrior books, with a few Battletechs thrown in, now you will see Battletech books, not Mechwarrior. But checking out Amazon, lists a few dozen entries to the Mechwarrior series of Pen and Paper/Table Top games (The first series of books has the full Battletech name, while Dark Ages still sports the MW name). Its a messy system, with two names.

Still the point is valid, the OP may know it by the name Mechwarrior as opposed to Battletech.

I think it might have been the Mechwarrior RPG 2nd Edition rule book. https://www.amazon.com/Mechwarrior-Battletech-Role-Playing-Game-2nd/dp/1555601294

For manuals I'd look at the Mechwarrior 2nd edition (main book) and the Mechwarrior Companion. Those two will have the bulk of the rules for the RPG side.