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I almost hate to say it around here but I think the D20 universe is wrong for Tolkien. Iron Crown Enterprises did a marvelous Tolkien rendition up until they lost\couldn't afford the franchise. Its still my choice for tolkien. Sad to say they are not in production anymore but you might still be able to scare up old copies on Ebay or find pdfs.
D20 is way too active magic rich, and twitchy. Tolkien's backstory plays out in hundreds and hundreds of years with most of the magic much more subtle than magic missle and fireball. D20, perhaps by virtue of its popularity, can be everything to everybody but seldom reserved.
Tolkien the D20 Version.
1) Gandalf tries to teleport to mount doom with Frodo and finds that the way is blocked.
2) Gandalf hides Frodo in another dimension.
3) Gandalf polymorphs Sam, Pippen, Merrydock and 3 more hobbits into flying creatures with instructions to fly to mount doom and drink a reversal potion - then summon him.
4) The six birds of the ring make their way with various mishaps to mount doom. 2 die at the hands of Sauron's minions. 1 is shot and eaten by Aragorn who has indigenstion but doesn't know why.
5) Finally Sam lands near the gate of mount doom before a small orc detachment. The orcs chase Sam for dinner but he transforms and summons Gandalf. Gandalf fireballs the orcs and clears the way for Frodo right up to the brink.
6) Frodo is summoned from another dimension and is told to dump the ring in the crevice. He makes his challenge role ( he is a hero ). Dumps the ring and Sauron Looses a whack of power.
7) Only this is D20 where powerful badies always seem to have more power to find. In the week since the adventure began Sauron has shifted focus from the ring and has an undead army and an alliance with Sauruman to fall back on.
S