Terry and Max's geeky friend Corey Cavalieri is obsessed with the virtual reality arcade game Sentries of the Last Cosmos, playing it so much that he has achieved the highest score in Gotham. Lamenting that his skills in the game do him no good in real life, he suddenly gets an invitation to Sentrycroft, the private estate of the game's creator Simon Harper. There, Harper inducts Corey and two other dedicated players as real Sentries, asking them to serve him in his ranks. However, the "missions" that the Sentries are given by Harper turn out to be various crimes, forcing Batman to intervene and investigate the matter.
- A God Am I: The idea of being "The Wise One" went to Harper's head.Terry: I don't understand why [Harper] did it. Didn't he have enough money?Bruce: It's not easy to give up being God.Terry: I suppose you'd know.
- Affectionate Parody: Mainly of the Star Wars franchise, but also other sci-fi series such as TRON and The Last Starfighter.
- And You Thought It Was a Game: Harper reveals to the Sentries fans that he keeps track of the game's high scores as a recruitment tool for new Sentries to serve under him.
- Anti-Escapism Aesop: Played with — it's not that being fans of the Sentries is a bad thing (Terry is one), but it's made pretty obvious that Harper's crazy little assassination scheme wouldn't have worked if the fans he recruited weren't on the verge of being Daydream Believer-types and bought his tale hook, line and sinker.
- Badass Boast: "Sentries to the challenge!"
- Complexity Addiction: Eldon Michaels wishes only 15% of royalties for the Sentries game, but this would mean that Simon Harper would lose the fame he's built as "The Wise One", so for Harper Murder Is the Best Solution. Instead of just asking Michaels to come to his manor and killing him, however, he decides it's best to do a whole scheme where he pretends to be leader for "the real Senties of the Cosmos" and convince some kids to go and kill Harper because he's supposedly some kind of Ultimate Evil and have them run around with the Sentries gear as some kind of field test. This not only attracts Batman's attention but eventually does an even better job of making him a Broken Pedestal than just paying Michaels would have been.
- Creator Worship: In-Universe example with Simon Harper, who is referred to by his fans as "The Wise One" and is practically viewed as a demigod by them. When Terry is bewildered as to why Harper would go through the trouble of trying to kill Eldon Michaels when Michaels had only asked for a mere 15% of the game's profits, Bruce speculates that Harper probably cared less about the money and more about the fan worship (which he would lose if it were revealed that he was not the original creator of the game).
- Indeed, at the episode's end, the fanboys seek out Michaels at his apartment, calling him the "real Wise One."
- Earn Your Happy Ending: The episode ends with Eldon's new found fans visiting him to return his script. They want to know more about his stories, and even though Eldon is a bit jaded, their view in him as "the real Wise One" reignites his creativity.
- Eldritch Abomination: Harper informs the Sentries that a figure named Eldon Michaels is the "Dark Regent," a grotesque alien monster that has disguised himself as a human. When Batman goes to investigate, he finds out differently:Eldon Michaels: (after being hit with a Batarang) Ow, that hurt!
Batman: (dumbfounded) "Ow, that hurt"?
- Comically Small Demand: All Eldon Micheals wanted was to be paid for the work he did for Harper. Which only came to about 20% of the profits. He was even willing to settle for 15%. However, it wasn't about the money for Harper. Paying Michaels for his work would mean revealing that he himself did not fully create the game as his fans believed and the near godlike worship he received from them would disappear.
- Fanboy: Corey, Dempsey, and Burfid, who dedicate their entire lives to playing Sentries of the Last Cosmos.
- Ascended Fanboy: After Simon Harper invites them to become actual Sentries working under him.
- Fictional Video Game: The episode's title. The game would later make cameo appearances in other episodes of Batman Beyond as well as The Zeta Project.
- Geek: Corey and the other Sentries fanboys. Eldon Michaels as well.
- Insufferable Genius: Eldon Michaels in spades. He is apparently the real creator of the Sentries game, having been cheated out of his share of the profits by Harper.
- Is the Answer to This Question "Yes"?: Terry answers a question by asking "Is Jar-Jar lame?"
- Jerkass Has a Point: As insufferable as Eldon Michaels is, he's still totally justified to demand his fair share for creating "Sentries of the Last Cosmos" and is genuinely Closer to Earth than Simon Harper, who let the fame and money go to his head.
- Mood Whiplash: When Batman sneaks into a house where he gets shot at by a menacing-looking shadow with glowing eyes. Batman goes on the offensive and disarms the assailant with a batarang, but...Assailant: (gun knocked out of his hand) Ow! That hurt!Terry: (dumbfounded) Ow that hurt?
- No Celebrities Were Harmed: Eldon Michaels appears to be partially based on George Lucas, as well as Gary Gygax and Bruce Vilanch. Simon Harper as well, since his "Sentrycroft" estate is a clear parody of Skywalker Ranch.
- Plagiarism in Fiction: Simon Harper stole the idea for "Sentries of the Last Cosmos" from Eldon Michaels.
- Shout Out:
Max: He invited Corey to come and meet him. Do you think there's a connection?
- In explaining the story of the series to the fans, Eldon Michaels begins, "It all started a long, long time ago, in a Cosmos far from Earth...".
- In the climatic battle with Batman, Harper is dressed in a dark hood and shoots blue lightning from his hands.
- Earlier, while playing the game, Terry yells "I can't shake him!" in reference to some enemy fighters.
- This exchange:
Terry: Is Jar-Jar lame?
- Eldon Michaels' typewriter, which Terry mocks (and eventually uses as an improvised weapon once the Senties come a-knockin') has quite the history: Michaels says that it belonged to Philip K. Dick.
- Something Completely Different: Even though it's still believable with the setting, the episode gives us a sort of TRON/Star Wars/The Last Starfighter plot.
- What Are Records?: Not records, but in the same spirit of the trope: Batman goes to the home of Science Fiction writer Eldon Michaels and finds a typewriter. He pokes at it and asks, "What is this? Some kind of word processor?"