- Middle-earth Role Playing
- Lord of the Rings Adventure Game
- The Lord of the Rings Roleplaying Game
- The One Ring Roleplaying Game
- 5e Adventures in Middle-earth
There are definitely Middle-earth products which use the Rolemaster system alone because they predate the MERP system. MERP is nothing more and nothing less than a lite version of Rolemaster. Once MERP was published, all Middle-earth products were dual-statted for RM and MERP, and also, all non-Middle-earth products were dual-statted for RM and MERP. LOR (#3) is an even liter version. Once it came out, all products were triple-statted for RM, MERP, and LOR.
If I had to pick one of the above with which to run a straight game, it would be RM with MERP’s simplified combat system but retaining RM’s classes and spells. The ICE support products make up a gigantic resource that is obviously unparalleled by the later games.
I like LotR (#4) for its magic system.
In practice, I use AD&D/1E as my baseline and incorporate bits I like from the above.
I would really love to love TOR, but I really don’t. Maybe it will be worth another look in 5 years, if it will be more of a toolbox by then and less of a straightjacket.