Patton Oswalt's interest in comic books and genre material has been well documented -- look no further than his adlibbed eight-minute Parks & Recreation filibuster detailing how to merge the Marvel and Star Wars universes. The actor, writer and comedian became a voracious comic reader, eventually penning a few stories across DC Comics, Dark Horse and Marvel. Oswalt has also appeared in several comic book adaptations, including a live-action role on Marvel's Agents of S.H.I.E.L.D. and voice work on Teen Titans Go!, Spider-Man and Happy!.

What fans may not know is that he also appeared in several minor parts in the ground-breaking DC Animated Universe. Oswalt was credited on several episodes of Batman Beyond and Static Shock -- roles that indirectly set him up for a bid to write the Justice League Unlimited tie-in comic. The latter only resulted in the sale of a single unpublished story, but the story of how it happened is still one worth telling.

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Oswalt DCAU Specs Eldon Michaels

Despite being a well-received comedian with writing credits for Mr. Show and MADtv under his belt, when Oswalt guest-starred in Batman Beyond's "Sentries of the Last Cosmos" in May 2000, he was best known for his supporting role as Spence on CBS' sitcom The King of Queens. His appearance on Batman Beyond (before its comics reboot), besides being his first time voicing a character not based on himself, was rather fitting for Oswalt's career trajectory and interests.

As Eldon Michaels, Oswalt played a cross between Star Wars creator George Lucas and turn-of-the-century celebrity internet critic Harry Knowles. The creator of the "Sentries of the Last Cosmos" video game, Michaels had been shunted aside by his former business partner Simon Harper, who'd come to believe the game was real. This led to future Batman Terry McGinnis fighting Harper as an ersatz version of Star Wars' Emperor Palpatine. Michaels' stake in the "Sentries" games was reaffirmed at the end of the episode, and the game would appear in later episodes of Batman Beyond and its spinoff The Zeta Project.

Six months later in November 2000, Oswalt made his first of several appearances on the Kids' WB superhero series Static Shock as Specs. Introduced in the episode "The New Kid" as a student of the elite Vanmoor Institute, Specs and his friend and classmate Trapper (Michael Rosenbaum, who's currently developing a Smallville animated series) were enlisted by Edwin Alva to capture Static. Originally set apart from other DC animated programs -- as the original Milestone comics and their most recent revival are -- Static's second season linked it to the greater DCAU through a guest appearance from Batman. Specs made two additional appearances over the four-season run.

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Justice League Unlimited comic

Oswalt's prolific writing career had branched into comics around this time, notably at DC with contributions to Batman's 600th issue and 2003's JLA: Welcome to the Working Week one-shot (with then-newcomer Patrick Gleason). With those and a few other titles under his belt, Oswalt submitted a pitch to take over writing duties on Justice League Unlimited, the tie-in comic running concurrently to the 2004-2006 Cartoon Network series. Oswalt discussed his fondness for the series in a 2006 interview with Comicon's Pulse, mentioning the scope of the series, the variety of its cast and its handling of its villains among his favorite aspects.

Only one of Oswalt's ideas was bought (as he put it, "they thought a lot of my story pitches blew"): an issue pairing up time-traveling hero Booster Gold with the futuristic Atomic Knights. This may be less reflective of the quality of Oswalt's writing and more about the concerted move away from a regular creative team on the title -- a shift made following the exit of original JLU writer/artist combo Adam Beechen and Carlo Barberi. Nevertheless, Oswalt's issue went unpublished in the two years prior to JLU's cancellation in June 2008 with its 46th issue.

Patton Oswalt's star has continued to rise since his fleeting experience with the DCAU. He's since appeared in other DC Comics animated series, including The Batman as the Toymaker, the 'anything-goes' Justice League Action as Space Cabbie, and on Teen Titans Go! as the Atom. It took a little longer for the "distinguished competition" to knock at his door, but Oswalt voiced Uncle Ben in 2017's Spider-Man and starred as MODOK in the stop-motion Hulu animated series. Oswalt's time with the DCAU was brief and could have amounted to much more, but as a singular talent and professed super-fan, it's fitting he crossed paths with the seminal animated universe.