As Flash and his friends try to figure out what's wrong with him and the Omnitrix, they are faced with one of their greatest threats yet when Ghostfreak escapes from the Omnitrix, and reveals himself as the very threat Flash's future self warned him about: Zs'Skayr!
- Actually a Doombot: Azmuth surmises that since an Ectonurite's consciousness is in the smallest sample of their DNA, the Zs'Skayr that escaped from the Omnitrix is actually a copy of the original that was created when his DNA was collected.
- Antagonist Title: The title refers to Ghostfreak, and after he escapes from the Omnitrix and reveals himself as Zs'Skayr he becomes the main antagonist of the chapter.
- Bittersweet Ending: Zs'Skayr is defeated and destroyed, and although Flash lost his newest alien Ghostfreak, Azmuth plans to eventually re-add it back to the Omnitrix once he's sure it's safe. However, the ending scene shows Negatine in prison, exactly like he wanted to be, preparing to leave after he has what he needs. Also, Flash knows that he hasn't seen the last of Zs'Skayr.
- Body Surf: During the fight with Zs'Skayr, the Ectonurite takes control of each one of the Rainbooms in turn and uses their respective magic against the others.
- Brick Joke: When the sun is blocked by a cloud again after Zs'Skayr escapes, Flash asks if anyone knows a place with barley any clouds and lots of sunlight. Twilight jokingly answers the Sahara Desert. During the climax when the trap against Zs'Skayr fails, Flash has Azmuth teleport them both to the Sahara, where Zs'Skayr is destroyed by the sunlight.
- Demonic Possession: Zs'Skayr possesses multiple people throughout the chapter, including a random citizen, all of the Rainbooms, Trixie, Shining Armor, and Adagio.
- Disc-One Final Boss: Zs'Skayr, the villain that Flash was warned about by his future self at the start of the season, is dealt with here. This leaves the team of villains and the mysterious mastermind behind them as the true main antagonists of the season.
- Fight Off the Kryptonite: Zs'Skayr has a weakness against direct sunlight. With that in mind, Azmuth prepares a trap or him, a UV cage specifically designed to trap him even when intangible. However, Zs'Skayr is able to escape from the cage by forcing his claws through the energy field, even as they are burned in the process, and destroys one of the projectors, forcing the others to shut down.
- Fighting Your Friend: Flash is forced to fight his friends as Zs'Skayr hops from body to body, using their various powers against everyone.
- Hates Being Nicknamed: After Ghostfreak escapes from the Omnitrix, he yells at Flash to stop calling him "Ghostfreak" since that's not his real name, and announces his real name is "Zs'Skayr". This backfires, since Flash remembers what his future self told him and knows what his weakness is.
- Hope Spot: During the battle with Zs'Skayr, he possesses Sunset while jumping from body to body in quick succession. This briefly gets everyone to think they have an opening since unlike the others, Sunset's powers aren't built for fighting. However, the possessed Sunset runs around throwing kicks, chops, and judo throws at them. Sunset had apparently been taking self-defense lessons without telling anyone. But to be fair, how was she supposed to know she was going to get possessed by an evil ghost alien?
- Mythology Gag: Azmuth notes that he didn't intentionally sample Ectonurite DNA and that it just appeared in the Codom Stream, with him surmising that Zs'Skayr must have been possessing an alien that was sampled and his went along with it. This is what was mentioned of Zs'Skayr's backstory in Ben 10 trivia.
- No-Sell: Zs'Skayr can't possess Flash as long as he is in alien form.
- Save the Villain: When Ghostfreak begins to subject Negatine to a No-Holds-Barred Beatdown, Trixie and Shining try to restrain him before being thrown off, and Rainbow just grabs Negatine and runs him to the nearest police station.
- Sixth Ranger Traitor: Played with, in that Flash explains that he has always considered his alien forms were partners to him that he could trust and rely on. Having one of his forms, Ghostfreak, his newest form, betray him, is a deep cut for him.
- Stop, or I Shoot Myself!: Played for Horror when Zs'Skayr possesses Twilight. Taking Shining's Multi-Striker, Zs'Skayr points the weapon right under Twilight's chin. He threatens to pull the trigger, since he can easily survive by exiting the body, but Twilight obviously won't survive, unless Flash stands down, essentially forcing a Hostage Situation. Flash throws the sun-gun he was holding away and holds his hands up.
- This Cannot Be!: Azmuth gasps "Impossible!" when Zs'Skayr manages to destory the UV cage they trapped him in by fighting through its effects.
- We Will Meet Again: As Zs'Skayr is destroyed by the harsh sunlight in the Sahara Desert, he swears to Flash that he'll be back. Flash knows that deep down, he means it, but declares he'll be ready for him when it happens.
- Wham Line: In-Universe, where Ghostfreak reveals his true name is Zs'Skayr, with Flash realizing he was the threat his future self had warned him about.
- Whole-Plot Reference: To the Ben 10 episode of the same name.
