well...they did cut off Claire's head in Mama Petrelli's dream sequence.
Mal ,'Safe'
Heroes 1: We Could Be Heroes
[NAFDA]. This is where we talk about the show and ancillary materials such as web comics! Anything that's aired in the US (including promos) is fair game. No spoilers though -- if you post one by accident, an admin will delete it. Chuffa, Chuffa!
in reality! I want it done! canon!
I have been waiting for Sylar's head to be cut off for years.
But you know that, given the history, his body will just regenerate a new head or something. In fact, it's entirely possible that his head will regenerate a new body. Then there's gonna be two Sylars running around and no one will think they can kill either of them but they'll talk about needing to kill The Sylars a LOT.
Has Claire ever completely lost an appendage? I mean, she's had fingers almost cut off, and she puts them back on and they heal, but has anything ever been completely cut off?
Maybe the Sylars would each be so power mad that they'd kill each other.
The top of her head was completely cut off. It's not an entire appendage of course.
Didn't Claire cut off her pinky toe?
Yes, Claire cut off her pinky toe while Stalker Boy watched.
I also think that Parkman could conceivably shut down the parts of Sylar's brain that give him his powers (even the regeneration he learned from Claire), and Peter could theoretically do the same. (Also, though he and Sylar are both immune to their own versions of Ted's radiation powers, we haven't seen proof yet of any particular resistance to the other's. Another Fat Man & Little Boy meltdown on Peter's part might leave Sylar as nothing but vaporized molecules incapable of reassembling.)
I'd favor encasing Sylar several feet deep in concrete, since as far as we know he still can't teleport.
Getting rid of Future!Peter might be a bit harder. The phrase "Nuke him from orbit. It's the only way to be sure" springs to mind.