You sure like to boast Zanaken but I believe you do know the character and I wonder if you have any tips on the MU vs Nightmare. I'm not talking about how to punish this or that move but let's say general advice. What's the most reliable way to face an aggressive Night.
Also I tried to B+K Night's BE ( the earthquake attack you mentioned in an older post ) and couldn't figure out how it supposedly stops it. What did you mean ?
this MU for me all comes down to how well you can pick off the little things all the while working in little things of your own.
because it's Raph, first thing anyone will do is step left, so integrating things like 2A, SE A, 2K etc will be a must.
and also NM is unsafe as shit, having an i12 punisher with THAT much range...man.
also I seem to notice your tendencies to go into SE needlessly. It's awesome for spacing and evading moves yes, how careless use ends up with you eating FC3B everytime.
imo the key to the MU is to utilize your PREP mixups effectively, knowing when to be aggressive and knowing when you need to sapce, this may involve having to a take a bit of shit before you can deal it out.
PREP B(B) ~ PREP B(B) would be a good way to determine if you're opponent will crouch at the site of PREP. NM's FC3B will cop this off pretty easily and will also have the range to cop off SE also.
In that case PREP K will catch duckers and stuff FC 3B all the same, this is when you can work in PREP mixups.
if your opponent stands firm expecting PREP K then you can SE B/SE A if they step.
if they back up you can do PREP 4 to back up also and create space.
also as Zannykins has stated NM's doesn't have a "be-all-end-all" move to stop all of Raphs stance transition, FC 3B won't work 100% of the time, 66K won't work 100% of the time and neither will 9K work 100% of the time