Bloodline Baby Tobirama
AU where Tobirama is found in a bloodline thieves base when he's an infant.
The Senju clan are the ones that raided them after they tried to snatch some of their members (the Senju may not have a prevalent Kekkei Genkai like the Uchiha or the Hyuuga, but they're all rather hardy people with good chakra stores, which is a desirable trait when you're looking to breed powerful ninja).
They find him after the fight and figure "well, he looks kinda like a Hatake?" so they grab him with hopes of strengthening their alliance with the Hatake clan by returning one of the kids they're notoriously protective of.
Only, he's not a Hatake. None of the Hatake recognize him at all, and no one has gone missing anytime in the last few years, not to mention he doesn't smell like a Hatake. So now the Senju are stuck with a random baby.
Butsuma just kinda shrugs and decides that they can always use more cannon fodder soldiers. He plans to give the baby to some other minor family to raise, but his wife calls dibs before he can.
That's the backstory to how he gets to his place as the second Senju son in this AU, though I imagine he's not technically part of the line of succession until after Kawarama and Itama die and Butsuma needs a second heir so that Hashirama will already have one when he takes over.
Now the main thing I wanted this AU for is that it lets us give Tobirama have any Kekkei Genkai we want (-Hatake, Senju, and any clan that has prominent physical bloodline traits ig?)
The obvious route would be "He's an Uchiha with Albinism", which is why they don't recognize him, but I know Tobirama-With-a-Sharingan is done pretty often, so I feel like doing something different.
So... How about Tobirama with the Ketsuryūgan?
I know in a lot of Tobirama fanfics he's able to manipulate blood, but I don't think that's possible in canon unless you have a Ketsuryūgan. I don't mind it because, well, it's Tobirama, if anyone could figure out how to manipulate blood even without a Kekkei Genkai, it's him.
OR! If we want to get even crazier (and way less canon, since it's only from a single anime filler arc) we could give him Ranmaru's Kekkei Genkai (it doesn't have an official name), which, from what I can tell is pretty much "make this throwaway character have cool abilities with undefined limits far past what's reasonable", and I think it'd be hilarious to see the Uchiha Clan's reaction to it.
If you want an idea of the unnamed Kekkei Genkai's abilities, it seems to be similar to the Byakugan in that it can see (and hear?) from miles away and through objects, and like the Sharingan it can predict movements, but it can also track chakra signatures, counter genjutsu being cast on the user, mask the user's chakra, make fake chakra signatures, use red dust to effectively negate other dojutsu and even read thoughts!
Yeah, see what I mean about insane abilities?
And guess what it looks like! ...It's just a red glowing eye. It's got no huge transformation, it just glows red. That's it. no swirlies, no bleeding, no nothing. Just... red glow.
Also Ranmaru is from Kiri, so Tobirama having a water nature makes even more sense!
Tbh I'm growing attached to the idea, just because of how insane the Uchiha would get about it like "wHAT DO YOU MEAN YOU CAN MAKE OUR SHARINGAN STOP WORKING?!"
I think Izuna would have a fit. He cannot believe his rival is doing this to him! How dare he! Stop cheating, Tobirama, it's not fair! he's supposed to be the one with the cool Kekkei Genkai, not you!! >:(
Yeah, it'd definitely end up becoming a bit of a crack fic in my hands lol
