Ryan McAvoy said:
A question:
I always remember growing up with the image of Anakin and Obi-Wan dueling in a Volcano (Or at a push a lava planet) firmly fixed in my mind. Me, my brothers and my friends. So where did I get this notion from? An article? A EU book? An interview?
In 1983 I picked up a so called Story Treatment that was being sold at the dealers tables at a Science Fiction / Comic Book convention in New York City. The treatment was titled "Episode III - Fall of The Republic". That is how I found out abut the Volcano fight between Vader and Obi-Wan back then. No it was not official, but I was not aware of that fact when I purchased it.
DISSOLVE TO:
SCENE 1: Sigma Vulcanus -- a new, evolving world, that is con-
stantly being shook by violent earthquakes and volcanic
eruptions, and which is devoid of sentient life-forms.
On the molten, volcanic world of Sigma Vulcanus, Anakin Skywalker, a handsome, swarthy man with a dignified stature, makes an important discovery. Using his lightsabre (as the equivalent of a divining rod), he uncovers the legendary Kaiburr Crystal. It pulsates with energy and fills Skywalker with a false sense of power and importance. But before he can savor his triumph, and return the Crystal to Palpatine, he is confronted by his old friend, and fellow Jedi Knight, Obi-Wan Kenobi and requested to explain his actions. Anakin refuses, and instantly, the two knights draw their lethal weapons and become locked in mortal combat.
Anakin Skywalker, as if controlled by another force, strikes swiftly in rage, but Obi-Wan Kenobi, the more experienced Jedi, easily deflects the furious blows of his young opponent. "Let go of the Crystal, my friend! Its power will consume you and turn you against the Jedi Knights," Kenobi explains. But the words are un-heeded by the young Jedi, and the conflict continues.
Skywalker attacks Obi-Wan again, forcing him to discard his defensive posture. Kenobi parries the thrust and sends Anakin's lightsabre flying out of his hand. At precisely the same moment, a cataclysmic earthquake rocks the planet. The effect is devastating: fissures, in the earth crack open and spout walls of flame; thunder and lightning strike violently from the sky; and several volcanos burst and bubble.
The young Jedi struggles to regain his lightsabre, but loses his footing and plunges, still in possession of the Crystal, into a pit of molten lava.
Kenobi hurries to the edge of the volcano and looks down; but he is too late to save his former friend: Skywalker is completely engulfed in lava! With tears in his eyes and anguish in his heart, Obi-Wan picks up Anakin's lightsabre and bids a sad farewell to the body of his friend.
Source = http://www.yodajeff.com/fanfiction/stories/republic.shtml