User blog comment:Berserkchart486/Warring States Fanon Canon/@comment-6673974-20141225023253/@comment-25152698-20141226202202

I'd say just keep it reasonable. I've already seen fanon kgs and such being made, which are definitely allowed, but as I just said, be reasonable about it. That being said, anything that was close to extinct in the actual canon should be gone now. Shikotsumyaku, Wood Release, the sharingan, most likely even dust release, since onoki was the only person seen who had it that was still alive. You get my point.

Anything that was common, such as the Byakugan, considering all full blooded Hyuga were born with it, would now be "rare", seeing as though a big part of society has been obliterated.

As far as space time goes, yeah sure you can bs a Jashinist uchiha who hid in his kamui dimension for hundreds of years, but obviously things of that nature just wouldn't get accepted, lol. The only canon spacetime techniques, ftg, kamui and the Kaguya Portal, are essentially unachievable at this point.