[[WMG: Neco Arc Chaos and Neco Arc Destiny have a sexual relationship, unbeknownst to the other Neco spirits.]]
This is hinted at in Episode 6. Neco Arc muses on whether the Neco spirits are siblings since they all have the same face. Some ominous music comes up, making both Neco Arc and Neco Arc Babbles very nervous, although Neco Arc Chaos and Neco Arc Destiny don't show any visible reaction. But the implication is that if that were so, [[SiblingIncest something would be very wrong ...]]

[[WMG: The other Neco Arcs are not new characters]]
* Neco Arc Destiny is Ichiko, Arihiko's sister. Working as a Neco Arc in Ahnenerbe is, in fact, her mysterious job.
* Babbles is Len. Because once a cat has been created, any universe would conspire to make it even more of a cat.
* Evolution is not a Neco Arc at all; he's just someone (possibly Mikiya from ''Literature/KaraNoKyoukai'') cosplaying as a cat.

[[WMG: Neco Arc ''is'' Avenger]]
Think about it. This solves EVERYTHING.
** Then explain why we see him sitting next to Roa outside the party in the final episode in the final scene while Neko Arc herself is clearly inside, would you?

[[WMG: Episode 6 ABSOLUTELY PROVES that Zouken does not exist outside the Heaven's Feel route.]]
This is [[SarcasmMode obviously canon]]. In this episode, Zouken is conspicuously absent, but most importantly, we see Rider's status screen. Her name isn't filled in and Shinji is considered her master, which is true all the way through to the Heaven's Feel route. This ''proves'' that we're not in that route, and Zouken not appearing means he doesn't exist anymore. He's not forgotten - he's there in the flashback - but he dies between then and the non-HF routes.
* Oh, he appears in episode 8, but so does Saber Alter. The latter [[InsaneTrollLogic proves beyond possible doubt]] that this is the Heaven's Feel route, justifying Zouken's presence.
* For all we know, Zouken doesn't leave the basement if he doesn't have to, as he's kinda old. And it's very likely that his inability to participate in the 5th Heaven's Feel in other routes was caused by him not succeeding at summoning True Assassin (which, along with Sakura not willing to fight, handicapped him greatly) and Ilyasviel always being closer than Sakura to defeated Servants (which meant Sakura wouldn't become the grail, and that was his ultimate purpose in the ritual [or so he thought]). And Taiga does mention in the other routes that she was talking with Sakura's grandfather, so he does exist there.
* Jossed. Zouken shows up in Fate/Zero, which is compatible with all routes.
** And ''double'' Jossed by Hollow Ataraxia.

[[WMG: Phantasmoon is [[RageAgainstTheHeavens Raging Against the Heavens]]]]
Her enemies, CardCarryingVillain Akiha aside, tend to be anthropomorphic mushrooms. Say, just like the AuthorAvatar of universe creator Kinoko Nasu...

[[WMG: Arcueid used her Marble Phantasm in the volleyball game]]
Just to screw with Ciel.
* She uses her ultimate ability, the power to [[WindsofDestinyChange alter probability]], just to troll Ciel? That's actually quite plausible.
* This is the same girl who repeatedly smacked Ciel in the face with the ball, despite being on the same team, and flat out admitted that she was doing that on purpose a couple of minutes ago.
---> Ciel: "You're doing this on purpose, aren't you!?"
---> Arcueid: "Can you tell?"
---> Ciel: "Why you..."

[[WMG: Everything in Carnival Phantasm is all part of Arcueid's dreams after going to back to sleep after her true end in Tsukihime.]] obligatory Grimdark WMG.
* Nah, not grimdark enough...they're Sakura from Heaven's Feel, torturing Lancer after absorbing him.

[[WMG: Ahnenerbe is a TARDIS, and the cats are all Time Lords.]]
* Somebody had to say it.

[[WMG: The show is the result of the Servants meeting the goddess Nemesis and asking for what they were due: some fun]]
Nemesis is the goddess of Rightful Retribution, meaning she brings horrible punishment to the evildoers and happiness or good fortune to the good people, especially the ones who have suffered much. The servants had all suffered a lot in life, and when they met her they demanded the fun they were due for... And because of Nemesis' sense of humor and the fact they were owed a ''lot'' of fun, she created the crazy world of ''Carnival Phantasm'', bringing in the characters from ''Tsukihime'' because they were due some happiness too and she was already in the area.
* Lancers dies a lot because he told her to hurry up before their masters died of old age.

[[WMG: Casters Cosplay Fetish is Canon.]]
She would love to dress up Saber in her costumes, in fact she was the one who designed Saber Alter and Saber Lily. She would dress the other girls too if given half a chance.
** Confirmed by [[VisualNovel/FateHollowAtaraxia hollow ataraxia]].
*** Isn't FateHollowAtaraxia a "dream sequence", though?

[[WMG: The unseen character whose hand that Saber is reaching out for in the end credits is either Irisveil or Shiki Ryougi.]]
* The hand is clearly female from looking at it and, if the credits were longer the chain could easily continue on into Fate/Zero with Saber and Iris being the connecting points between the two. Or, the final hand is Shiki Ryougi's, representing the Origin of everything that the Nasuverse can be traced back to in the end.

[[WMG: Like with Fate/Hollow Ataraxia the events of Carnival Phantasm are caused by Rin performing experiments on reality.]]
* Since Hollow Ataraxia strongly implies that Rin is responsible for all of the scenarios coming together, what's to say she hasn't been conducting more of the same experiment?