More about Diddy vs. Snake on Rainbow Cruise.
I got some experience about this stage today. I suspect this post may be quite lengthy, so yeah.
Counterpicking Rainbow Cruise on Snake has great rewards but is pretty risky, because while you have ease with some things, Snake also has ease with some things (re: killing). If you just counterpick this blindly, you may be surprised of some of the things that happen to you. But with some basic knowledge, the match should be pretty much easier for Diddy.
Rainbow Cruise is already a good idea for a counterpick on a campy Snake. Because of the moving level, his camping game is completely gone. And for these same reasons, he has much less time to rely on Claymores and C4s. However, against a regular Snake, this could be a pretty valid option as a CP too.
Good things:
1) Snake becomes a bit more predictable/readable on this stage. Why? Well, because you've eliminated a lot of his options. It's easier to expect an ftilt, standard combo, or nair here, because he can't mix it up with his explosives.
2) Cypher. As you already know, there's a large chunk of time where you both have to constantly move up. Your standard jumps have decent height. His don't. Expect him to have to use his cypher a lot more, which is good for you.
A lot of Snakes like to do the same thing for the majority of the time they cut their cypher early. Some Snakes, like one of the people I was fighting on Wi-Fi right before I made this post, like to airdodge to cut their cypher. Some Snakes like to C4. Some Snakes like to nair or do a different aerial. If you can read what your opponent is going to do (and you have at least an entire game to do that) then this is a great CP. If they airdodge much, you can wait after the airdodge and do an aerial. If they like to do an aerial, you can either sheildgrab, or if they're in the air, wait after the expected aerial (a Snake is most likely not going to uair when you're below them) and do an aerial.
Here's a situation: you see a Snake use their cypher, so you jump up to the platform they're trying to get to. If you're not exactly sure what they're going to do, sheild. If they do nothing, you can grab and grab release them forcing them to either (depending on location) die or C4 themselves up and do damage to themselves. If they airdodge onto the platform so you can't grab them straight from the air, you can wait and grab, dtilt and grab, or do a dsmash or fsmash if they're at a high percent. If they do an aerial, you can sheild grab. Win situations.
The more predictable, the better. The more they cypher, the better.
Bad things:
1) The ship has small side blast zones. Be pretty wary of recovering from the ship, because you could meet a bair or ftilt to the face. This is, however, also a plus for you, because Diddy kills horizontally, and if you read cyphers you can get off a fair and kill them. But because this can go either way, you have to be wary of this.
2) The 35-40 or so seconds of the two minute cycle that you're on the top. This sucks. Get too close, and you either get utilted and die, ftilted and possibly die, or thrown and possibly die. The ceiling is really low up top, and because the level moves, you can be thrown or ftilted to the left and die pretty easily. While Snake can't camp as well at the top because it moves, he still has his explosives as a pretty viable option.
Seems pretty bad for Diddy, right? Only real boost up here is that your bananas can be used more. Up here, being aggressive isn't the best idea, especially if you're at high percents. Even percents of like 50-60 can get you killed. You could be a little more offensive if you're at lower percents, but just be aware of the dangers.
Spacing is also pretty crucial. In the matches against Snakes on RC that I've fought, I've tried to space myself so that his tilts and standard combo can't reach well while I can throw bananas and get off the occasional peanut. Being just out of range also lets me get off a grab if he tries to pull out a grenade. However, I'd imagine you'd still have to worry about a dash attack or DACUS. The snakes I fought did neither, so I'm not exactly sure what to do if that happens....sheild it?
You could try staying completely out of DACUS range, essentially just running and shooting the occasional peanut. But this is pretty defensive, doesn't let you get off much hits, you still kind of have to worry about grenades and you can't punish them, etc. You could do this, but I wouldn't encourage it; if the Snake is already predictable/campy enough for you to CP RC and abuse his cyphers and other things, then you should be able to read him enough to be at a decent range.
tl;dr: If the Snake you're fighting is campy, counterpick here. If the Snake you're fighting is predictable, counterpick here. However, if the Snake you're fighting has a very strong game without explosives, or he's erratic enough that you can't always read him while edgeguarding, while close, while he cyphers, etc., you'd be better off counterpicking a safer stage like Smashville, Castle Siege, or Delfino's Plaza. You have an entire game, at the very least, to decide what stage you should counterpick.
...if you've read all of that, thank you. I'm still going to get more Snake stage matchup experience on this stage and Delfino Plaza. I love fighting Snakes, so I don't mind, lulz. But I can't wait until this discussion gets to Falco...I hate him so much, my worst matchup, much moreso than Weegee.