Most violent thing you've seen in a manga or anime

[Zero°]

ohhh, I'm reading Elfen Lied right now and there are plenty scenes, just havn't reached them yet (watched the anime)

I've seen all the episodes and, yeah, almost the entire anime is violent, but awesome at the same time :D

 

[幕之内 一歩]

While all the animes you've posted are violent in there own rights, I'm amazed none of you mention Berserk. You want gory and bloody? Then look no further. Also, another is Guyver. That anime is just full of guts flying every where.

 

[Deputy]

Berserk has some sick scenes but that's okay because it's Awesome.
Gantz is so bloody you don't even register the magnitude of the violence after a while.
Elfen Lied anime made me feel sick occasionally.
Battle Royale is just horrible though, every death is shown in disgusting detail, and not just random fodder, you actually come to like most of the characters, right before they get killed that is. Nevertheless it's still one of the better manga I've ever read, I should reread it sometime soon.

edit: Lol forgot to mention Hellsing.