Leroux: I would have said
Middle Earth: Shadows of Mordor, but it actually has next to no connection to the Lord of the Rings and is a better game if you ignore that its title is claiming otherwise. The story is rubbish but the gameplay is fun.
So I'd say
Lord of the Rings: War in the North.
Neverwinter Nights once had a pretty nice Persistent World server called
Untold Tales of Tolkien. That was cool too, especially the Hobbiton areas, but I think it's not live anymore.
Oh, and not quite LOTR, but
The Hobbit was an enjoyable platformer / action adventure. Too bad there was no digital re-release on PC so far.
Well, I'm no purist. If a game is fun and doesn't 100% undermine Tolkien's work, I'm fine with it. Fan-fiction can be entertaining. Anyway...
...
Shadow of Mordor is a great game.
Shadow of War is good too... but... a bit too much of same. Still, worth having and playing. Have to chuckle when I see their Shelob. ha.
I loved
War in the North. Still play it on PS3. Wish this new
Dungeons & Dragons Dark Alliance game took a note from WitN and had ally AI.
Mentioning all of these makes me sad that licensed games often has accessibility issues in old age. Once that license expires, many of these games are removed from storefronts never to return. Sad... would be great to see some of these here on GOG