Assassin is KiritsuguIsn't it obvious? Obviously confirmed.
Luvia will kill Assassin!KiritsuguHer contract was to kill the Magus Killer and she'll fulfill it by killing the original one and not Shirou. After all no one knows Shirou Emiya is the Magus Killer and no one would put a contract for a dead man so the contract was simply "to kill the Magus Killer".
- Jossed as of Chapter 44. There was a more standard loophole, allowing her to bail out of the contract if killing the target was obviously more inconvenient to every party involved.
Assassin!Kiritsugu will trick Witch!Caster into using up all her Command SealsShe's already had to use one just to get him to listen to her commands at all. Add one more to make him willing to fight his son, and a third to make him willing to fight his daughter, and suddenly Caster will find herself facing a very unhappy Magus Killer.
- Caster wasted the second one to get control of Rider. Now Caster has Three servants that want to kill her and only one command seal. She is not happy to say the least...
- Jossed as of Chapter 43. Caster now has access to Kotomine's stash of Command Seals.
Shirou's completed version of Unlimited Blade Works in this fic will be far more powerful than the versions from canon.Even in its incomplete state, it was rather similar to what it was in canon. Emphasis has been placed on the fact that it is regarded as a memorial for heroes, their weapons littering UBW's landscape. When this version of Unlimited Blade Works is complete, it will go beyond being a landscape full of blades, and allow Shirou to summon a shade of a Hero that owns a particular weapon within his Reality Marble. It's mostly baseless conjecture, but it would make for something interesting, and allow for cameos of other Servants from other Fate works, or perhaps even an appearance from a certain recently deceased King of Heroes.
Taiga has a more active role than in Canon, and knows at least part of what is going on.
- The still-unnamed character who observed the battle at the Temple.
- Taiga actually cheering up Shirou in a flashback described in Chapter 45. This hints to her knowing far more about Kiritsugu's past and maybe Shirou than she lets on.
Shirou hates Archer and wants to kill him for "what he has done" on an instinctual level. What he has done is killing Sakura.
- Fact: Killing or betraying Rin or Sakura is excruciatingly hard for FFD!Shirou since they are keystones to his Reality Marble. Archer, being himself, does not have this constraint.
- Fact: Even FFD!Shirou's base instincts as a STARVED and DYING blood-thirsty Apostle will NOT allow him to lay a hand upon Sakura, PERIOD. That is how anathema hurting Sakura is to Shirou (barring the one case he had to skewer her with Gae Darg to save her, and he did not exactly feel good about it) on a subconscious level.
- Fact: Archer having a resonance with FFD!Shirou was actually a learning experience for him this time, prompting a strange reaction to something he said he figured out after thinking about how he gave his arm to Shirou in Sakura's route, Heaven's Feel. He muses that he now has knowledge he wishes he could have put to use in context, and further how it should be IMPOSSIBLE for him to actually know about the whole transplant thing, since he DIED at this point in that route.
- Conjecture: Archer most likely had to kill her in one of his summonings, or even in his initial life in the yet unknown Archer/Illya route, and thinks nothing of it since he did what he had to do, the very attitude Illya calls him out on.
- Confirmed: Shirou goes into such an Unstoppable Rage Rin has to threaten his kitchen to allow him to at least ally with Archer temporarily.