MichaelSomething
Legend
To my mind Tolkien presents three major problems for an RPG adaptation:
1. It is a lore that many people respect and sort of know, but few have the patience to master the extreme complexity of. This makes it sort of the perfect storm of difficult to manage on the world-building front. There are authoritative correct ways for almost everything in Tolkien's world to be, and players will likely care to some extent, but it's difficult knowledge to master.
2. It is a legendarium built around the several stories Tolkien wanted to tell, and he has told them. For all the richness of the setting it's actually a harder setting to tell additional stories in than most, because the whole world revolves around Morgoth and the Silmarils, and Sauron and the Ring. Even Tolkiens own side story of The Hobbit he eventually felt the need to weave into the grand epic of the Ring. The degree to which the whole worlds revolved around the rise and fall of these villains is much of how Tolkien makes these almost entirely "off-screen" figures compelling villains.
3. As several people here have pointed out, a key part of the feel of Tolkien is that he focuses on the hobbits, who, while I would argue that they "level up" more than some people in this thread have given them credit, they are still not turning into anything but the most reluctant action heroes. TTRPGs tend the focus on the people willing and capable of going on adventure, and generally a problem one has to fight is players wanting to create reluctant heroes like those they see in books and movies and it then being on the GM to thrust adventure upon them against their character's preferences. RPGs tend to work better when they focus on characters like Legolas and Gimli who, sure they have a quest, but at the end of the day they both seem to just enjoy adventuring for adventuring's sake, at least to some degree, and spent years traveling the world together after the quest of the ring concluded.
DM of the Rings I:The Copious Backstory - Twenty Sided
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