Dear god, what is the breakdown of ICs against ROB? That bugger seems tough to fight.
It's their second worst matchup, in my opinion (which changes day-to-day). You get camped really hard, and can't keep up pressure for too long because of his dsmash. Your best option is to powershield something and get a grab on it (yea, I'm aware that sounds like every other matchup). If you get dsmashed, SDI TOWARDS NANA AND HIT ROB IMMEDIATELY, if you don't Nana is dead, and there's nothing you can do about it. If you get ROB on the ledge, blizzard pressure works pretty much the same as tornado pressure, keep a blizzard on it, and he'll rack up damage and be forced to recover way over you, which is the only place you have advantage in the matchup, because IC uair is disgustingly good against ROB. I've made ROBs run out of fuel with blizzard pressure on the ledge, it really hurts him. If you get just a little ISSDI on his dsmash and buffer a dash grab OOS, you can get the grab on it. His ground game is better than the ICs, so you MUST get him in the air (smart desynching with blizzard). Don't approach with desynchs from any distance, you're going to get lasered and separated and lose Nana. Every single time you get separated, if the ROB is half decent, ROB is going to kill Nana, so be very aware of that. Oh, and at low %, you can land uair uair, hitlag desynch nair and footstool to ice block for a grab as a true combo, but that's rare and random.