Subaru recovering his memories will for sure help solve the challenge, since this Subaru doesn’t remember that speaking about return by death kills his enemy. He could use Satella to defeat Reid, if thats even possible.

We know it worked this way once, when it wasn't in Subaru's favor. There's no reason to assume Satella won't just kill Subaru this time instead if he tries solving his problems that way. She has massaged his heart threateningly in the past after all.

Shower thought that I had: what if there's more than one book? He's died several times after all. Imagine he found a book that just ends with Rem torturing him or something.

Probably not how it's going to go, but it's funny to think that it could.

It actually reminds me of the echidna route. It isn't necessarily a great thing, and realizing that he can't just be killing himself all the time was Major character growth a couple seasons ago.The reintegration of old Subaru and current Subaru is exciting, but I have to admit I don't know it's going to be effective. I don't know what information old Subaru would have that new Subaru is lacking.