Just wanted to say, I think the general soul calibur community as a whole, including the majority of 8wayrun, doesn't really understand the fine nuances of nightmare.
First of all, he is NOT bottom tier. Sure he's punishable, sure alot of his moves are slow, but with such a massive reward, it kinda makes up for it.
I've been playing nightmare since the beginning of sc3 (sc2 nightmare was a completely different character).
he is by no means weak. With him, you REALLY have to pick your shots wisely, not like amy or cassandra, where you can generally spam safe moves for the win.
the reason i would place nightmare in top tier, is because he will always push you to the edge of the ring whether you block him or not, and that alone puts fear into people to the point where they mess up trying to get away from the edge, or getting mixups left and right. playing against nightmare, you WILL BE AT THE EDGE OF THE RING AT SOME POINT IN THE MATCH!
playing against nightmare forces you to be almost as risky as nightmare himself. You need to NOT be passive against him by blocking him and instead throw in some counters.
On the other hand, when playing against a GREAT nightmare, i find myself blocking alot because at his range, he's incredibly fast. So really what i have to do is find an opening (which usually isn't a big window at all) and punish him.
I personally believe that the best nightmare player is extremely aggressive who doesn't mind risks, because ironically, the best way to play nightmare is to be RISKY, as opposed to most players, where the general strategy is to be safe.
I agree that playing nightmare is manly. Pure testosterone with a big ass sword.