He was introduced in New Teen Titans #2 (Dec 1980) as the butler of Deathstroke the Terminator. In later issues, and Deathstroke's own title, it was revealed that Wintergreen was a former member of the SAS who rescued Sgt Slade Wilson (the future Deathstroke) from a bomb, who in turn would rescue him from a Viet Cong prison.
Although Wintergreen did not have Deathstroke's abilities, he had more experience and often acted as his mentor. Since Deathstroke was devised as the criminal version of Batman, Wintergreen was his counterpart to Alfred.
When Deathstroke (temporarily) retired, Wintergreen honoured him by running Vigilance Inc., a search-and-rescue operation originally set up as a mercenary organization by Slade's ex-wife, Adeline. He was subsequently killed (and has his head mounted on a wall) when Jericho took over Slade's body and attacked him. Although Jericho was in control of Slade, Wintergreen apparently had believed he would be murdered by Slade eventually, evidenced by his apparent last words of "I suppose it was only a matter of time."
During the Blackest Night storyline, Wintergreen was reanimated as a member of the Black Lantern Corps, hunting down and attacking his former student.
Television
Wintergreen makes occasional appearances in Teen Titans. Unlike Slade, Wintergreen is never referred to by name. He is first seen in the episode "Divide and Conquer" when Cinderblock delivers Plasmus to Slade. He is almost never seen out of his master's lair except in "The Lost Episode" (which never aired on TV but was a promotional episode for Post Cereals) where he is part of the crowd running from Punk Rocket's Rock N' Roll rage. He later appeared as a member of the Brotherhood of Evil, participated in the final battle against the Titans, and was frozen along with the most of the Brotherhood, once they were defeated.
Bill "Billy" Wintergreen appears on The CW's live-action television series Arrow, portrayed by stuntman Jeffrey C. Robinson. He serves as the show's first incarnation of Deathstroke, and is as evenly skilled in swordsmanship and hand-to-hand combat as Slade Wilson is. In fact, Wintergreen's physical reflexes have been shown to borderline superhuman. Wintergreen was once a member of the ASIS' elite division known as Team-7, serving alongside his close friend, Slade Wilson. Wintergreen even served as the godfather of Slade's son, Joe. Bill and Slade were sent to the island of Lian Yu to rescue Yao Fei from a group of mercenaries that sought to cripple China's economy. But after their plane was shot down by the mercenaries' leader, Edward Fyers, Wintergreen defected to Fyers' side, leaving Slade to survive on his own. In "Damaged", Wintergreen is sent by Fyers to torture Oliver Queen for Yao-Fei's location at Fyer's tent, until Yao Fei launches a surprise attack and subdues Wintergreen. In "Year's End", Wintergreen rescues Fyers from Yao Fei's capture and bests the latter in combat. In "The Odyssey", Fyers orders Wintergreen to execute a captured Oliver Queen, but is stopped when Slade triggers an explosion as a distraction. Wintergreen and Slade then engage in single combat, and although Wintergreen initially gains the upper hand, he is seemingly killed when Slade stabs his right eye.
Video Games
In Batman: Arkham Origins, Batman's profile on Deathstroke says that William Randolph Wintergreen is an associate of Slade.
Merchandise
DC Collectibles released a Wintergreen figure in a two-pack along with Oliver Queen, based on the television series Arrow. This Wintergreen figure was marketed under the title "Deathstroke".
