Ok so the reason for nerf is that it works so good online and in offline tournaments on people that don't practice the matchup?
I've watch tournaments and I watch them all if I can, the only way where this happens is where people don't know anything about NM.
Sonic LOST to Nightmare AGA spam rofl. That's not Nightmare being overpowered, it's Sonic not knowing the matchup.
You're a Raph main? I also main Raph and Nightmare can't hold a candle, 3(B) destroys everything he does with TC and SC, each hit that puts him in a stance is guaranteed death for him and he can't even press any button without getting pulverized.
I've been playing Nightmare since SC3 and he is more or less identical in terms of safety and punishment. He is thought as a high risk high reward character and the risk is very much real as once one knows the matchup one can basically shut down everything but 3K and K.
SC on Nightmare? Hige blockstun and guard damage? This applies only on 6BBB as the other ones will never get out. Ever. Everything is interuptible, even 6KK, as I said. Any decent player with Nightmare matchup knowledge will always shut everything down.
If 6BBB is actually what the issue is with Nightmare (since I can't possibly find a scenario where anything else he has is actually useful) it's sincerely not a good argument. This vertical is very good, but remember, high risk high reward. Just do it and get sidestepped, it's RO time or 50%. There's no scenario that guarantees 6BBB for Nighmare, he just has to close his eyes and do it and hope for the best, which is exactly what the character is intended to have as design.
I'd complain more about SC KB if we need to actually pinpoint very strong moves as it gives a 2A+B on CH and you can endlessy continue doing so.