Darth Subeth was a very powerful Sith Lord during the 70s, 60s, and 50s BBY. He had originally been a Jedi, but he turned to the dark side and vowed to destroy all the Jedi, or if he couldn't accomplish this, at least train another so the apprentice could destroy the Jedi. For the duration of the 70s BBY and the first half of the 60s as well, none of the galaxy knew Darth Subeth even existed. During that time, he was training and building an army. This army became known as the Hidden Sith Army because Darth Subeth wanted the army to be hidden from the galaxy until it became big enough for conquest of the galaxy. And big it did become. By the time of the First Battle of Ris'danon, the Hidden Sith Army had 150 Dreadnaughts, many smaller support ships, as well as about 850,000 ground soldiers.
The First Battle of Ris'danon
After twenty years of pure training and building of his army, Darth Subeth decided to begin his plan to conquer the galaxy and destroy the Jedi. He sensed a presence at Ris'danon that was very strong in the Force, so Darth Subeth brought his army to that planet. When he arrived, he found that the battle had already begun. He sensed more than one Force-sensitive person on the nearest ship, so he ordered his army to fire on that ship. When the ship was destroyed, he still continued to sense a Force-sensitive presence however. And it was coming toward him. Darth Subeth realized from this that this Jedi was no ordinary Jedi. He came down to his ship's hangar bay to personally destroy the Jedi. There was no doubt from his knowledge of the Jedi Code that the Jedi would come into his ship to try to destroy him and the other leaders of his army. After only a couple minutes, a Jedi starfighter along with twelve Ris'danon Army fighters landed in his hangar bay. He hid himself so that Dak Jesser would get a safer feeling and possibly lose his guard. After letting Dak's squadron walk through Darth Subeth's ship for awhile, the Sith Lord revealed himself to them. Darth Subeth drew his lightsaber and activated it, using his other hand to surround his blade in Force lightning. He knew that Dak would realize his blades wouldn't do anything against the lightning-surrounded blade. Darth Subeth knew that when Dak realized that, the Jedi would use only the Force against the Sith Lord and he would die. Dak began the fight with a Force slam against the Sith Lord, but the slam was easily stopped. Subeth reached out with his lightsaber to strike, but it was only a feint, and Dak jumped out of the way of the lightsaber directly into a Force wave. Dak stumbled backward and Subeth struck out with his lightsaber. Even with Dak's mastery of the Negate Energy power, the lightsaber's energy combined with the pure Force energy of the lightning was too much for the Jedi. Just before Subeth could deal the killing blow, one of the members of Dak's group took a shot at the Sith Lord with his blaster. Subeth spun around and deflected the bolt right back at the commando, but the short distraction allowed Dak to power up and use Force Speed to get back to his ship and fly away. Darth Subeth, having never mastered Force Speed, could do nothing but take Dak's group as prisoners to use them as bait for Dak to return.
Powers and abilities
Darth Subeth was a master of the Force and also a very accomplished lightsaber duelist. Darth Subeth was a master of the Force Lightning power. He used this to his advantage. Whenever he fought, to scare his opponent, he would use his off hand to surround his lightsaber blade with Force Lightning. This added to his ability to win every lightsaber duel he had to fight.