Stark is the multi-billionaire co-founder of Wizard Computers. A ruddy man with a Scots accent, he co-founded the company with Bill Brower some time during the 1970s. Photos of him from the 1970s picture Stark as young and thin, with long shoulder-length red hair and a beard. His current physical incarnation is of a chunkier man with a short red-gray beard and almost bald.
While on a flight from Lawndale, he is saved from an assassination attempt by Jane Lane, Daria Morgendorffer, and Quinn Morgendorffer, all of whom had gained superpowers only days earlier. In gratitude, he decides to use the three to spearhead a youth organization called "The Legion," which he had always hoped of funding. He then disappears, leaving the girls with the power to control his vast fortune when they become old enough.
Stark only makes two more appearances in LLH: a surprise visit to the Legion at their Quarry headquarters and a visit to Kyle Armalin, which leads not only to a physical confrontation between the two, but with Armalin being asked by Stark to assist in training the Legion, after which Stark disappears again.
Due to legal troubles, Stark makes few appearances in LLH, but in the event of a dire emergency, Dawn Hall has his number and Stark will always be a phone call away if really needed.
Russell Stark was not created by Roentgen, but by a friend of Roentgen's who is now deceased. (RTB RIP.)
Stark's first appearance is in the episode, "Catholic School Girls in Trouble".
Russell Stark and Kyle Armalin encounter each other in LLH 7.1b ("Civil Defense"), but according to the text, this was not their first encounter. Their first encounter was sometime when Armalin was a young man; supposedly Stark has won both encounters.
In his second encounter with Kyle Armalin, Stark not only survived the confrontation (in which Armalin used his superhuman abilities) but bested him, leading many fans to suspect that he may not only be a superhuman but also a member of the Elite. If this is true, then the assassination attempt on Stark's life that resulted in the Legion's founding may have been an Elite operation. Thus, ALL subsequent attacks upon them (save the one initiated by a future Penny Lane) may be part of some unknown Elite plan, as they have shown in the past to have a singular goal of maintaining the complete ignorance of the general public to the existence of superhuman beings in real life.