Bowser is only a +2. We keep him out and we can mess him up off a grab, but our combo game is not as good as the rest of the cast (they deserve the +3). Also, our recovery is actually not hard for him to edgeguard
even if we go high. Also, Bowser can upB OoS most of our boost approaches.
Samus is closer to even for us. I'll just quote what I wrote in the Samus boards:
Samus:ROB is pretty even. I play both chars at a fairly high level against other good players of the other char (ROB against Minty and Samus against Rubba Prime). Both of them have good things on each other that are pretty equal in weight. Both can poke and CC each other pretty well as well as edgeguard each other pretty hard. ROB can juggle Samus, counter-zone her projectiles (laser beats everything and gyro absorbs missiles and Charged Shot), reflect her projectiles while approaching on the ground, and he can kill her off the top fairly early. Samus can zair almost anything ROB is doing, she can play for extended periods of time while holding onto his gyro, and she can kill off the top early with anti-air usmash. She can also pressure his shield pretty easily, since he has no good OoS game. His shield is also easy to poke, and he's pretty comboable for Samus.
I don't think we have a +2 on DK. I'm not even sure we beat DK at all; it's probably even. DK can CC grab/tilt all of our tilts, jab, DA, and fair, and he can also juggle pretty well, even against us. His grab game is extremely annoying when he gets in. DK also has a surprisingly effective edgeguard game against us. Invincible ledgedrop upB stuffs literally all of ROB's low recovery options. UpB in general really limits our recovery options, and he can bair and nair pretty far/deep offstage and still make it back okay. He can even go kinda far out with a big fair and still recover. At neutral, lasers can stuff him pretty well, but it's still pretty awkward to deal with his speed and big hitboxes. Most chars beat DK on the premise that they can combo and edgeguard him extremely hard, but our combos on him are not that great and our edgeguards outside of hitting him with dair are not very great either. The fact that we can't really reliably kill him until 150+% is a big problem.
Squirtle I feel is actually kind of even. He kills floaties kinda early with usmash, dthrow, and upB combos, and he has an interesting two-pronged bait mix-up on us. He has moves with enough armor (all of his shell moves) to beat our tilts and fair, but he's fast enough to bait out our bigger moves and punish them afterwards. Also, Squirtle's pressure on us is kinda crazy, if only because we barely have OoS options to begin with and they are definitely not equipped for handling Squirtle. His dtilt is super safe, and I'm not even sure if we can shieldgrab it (I think it might work against CC as well). His crawl attack has armor and crosses us up. I don't even have to talk about how helpless we are if Squirt is behind our shield. His SideB bounce also isn't really punishable by us, even if we try to CC it. People earlier were complaining about Sonic, well I feel our MU against Squirt is basically a MU against a slighter slower Sonic with bigger hitboxes, more kill-power, and armor. Still even 'cause Squirt is super light and easy to gimp also.
Mewtwo I think beats us at least -1, maybe even -2. He's good at killing floaties, he's great at juggling, he has good anti-airs in utilt/smash/air, he has a good edgeguard against us, he recovers fine against us, and funnily enough, he can punish us for reflecting his Shadow Ball if he reads it. This MU isn't a -3 because our neutral game is fine against him and we can kill him kinda early if we land a vertical KO move.
Link is weird. Even isn't exactly a bad designation for him, but I feel that he beats us -1. His projectiles are stupidly good at cutting off our aerial mobility, and our ground reflector isn't much help if he angles his 'rang and doesn't chuck his bomb the moment he pulls it out. He also does a decent job at keeping us out with with practically his entire moveset. Link also gets to shieldgrab us for spacing ftilt, so that's super annoying, and I believe he can walk forwards against a thrown gyro because of his Hylian Shield. His projectiles also make recovering really annoying since he can make a web with angled rangs, arrows, and bombs, all he has to do is tag a boost to make life scary offstage.
I also think we lose to Zelda. Our weight means nothing against her. She has good vertical KO moves and her kick doesn't care about weight. She has good anti-airs in usmash and utilt. She also gets a free kick if we ftilt her shield, even when spaced. She also recovers fine against us. At neutral, it is really awkward to deal with all of her BS. She can place her Din's Fire at heights that restrict our boosts but are also awkward for us to get rid of. If we try to boost over them, she can teleport under us and usmash/utilt or jump nair. Din's Fire also messes with our recovery (this is turning into a theme; our recovery is not as crazy as most people like to think). At neutral, Zelda can also reflect our projectiles and she can land-cancel said reflector to make it hard to bait and punish. What we get is that she is floaty, so vertical KO options kill her early. There's always the fact that Zelda can always transform into one of our hardest MUs at any given moment.
I already explained earlier why I think we beat Sonic.
DDD I feel might beat ROB +1. DDD has some strengths on against heavy floaties (ROB, Samus, Zard, etc). If ROB doesn't DI his dthrow perfectly down and away, he gets a CG across the stage. On top of that, DDD is a master juggler. He has plenty of moves that completely out-space ROB's entire moveset, so he can stuff boost approaches. From a distance, Waddles block gyro toss, and his ftilt vastly outranges ours. To top it all off, DDD can edgeguard us. He can go out incredibly far, use pretty much any aerial to challenge our boosts, and then still recover. Meanwhile, we struggle to kill DDD before 150%. Looks more like a losing MU to me.
Wolf is even or +1 for us. His blaster works better for us than it does for him, so his neutral game is basically him without a blaster vs us and our big hitboxes and great aerial mobility. We can gimp him and he's the only spacee whose shine we can CC. Also, Wolf's kill options aren't great against heavyweights.
G&W is -2 or -3. Literally beats everything we can do. Bigger hitboxes than us on all accounts. We can't really punish his crap. Combos us like crazy and kills us ridiculously early on whatever side he chooses. He also edgeguards us really well. He can beat us coming in high, and he can go extremely deep to edgeguard us with some huge move and still recover. Bacon also cuts off our boost options. Our bad tech-roll means that his dthrow tech-chase is effective on us. The icing on the cake is that he can bucket the laser and get a fairly strong Oil Spill off of only one absorption.
Falco is even for us. We have great gimps on him, and while Falco can also edgeguard us somewhat well, it doesn't quite match what we have on him (and he will have a hard time killing without gimps). His lasers aren't as bad as Wolf's blasters, but they are still very usable for us if we read them. In fact, his lasers are part of an interesting mix-up where we can mess him up if we predict a laser but he can bait a grounded reflector with an empty hop and punish the attempt. On top of reflection shenanigans, we can boost over lasers and threaten him from the air as well. We can also punish Falco trying to top plat camp pretty well with uair pokes.
Diddy I think might only be a -1 for us. If we read a banana toss with a reflect, then we mess him up. ROB uses items very well, so if we get a banana in our hands, our glide tosses can be almost as lethal as Diddy's. Also, we have more ability than most to simply avoid landing on a banana with boosts, plus we can easily boost over a banana and scoop it up with a waveland. Lastly, we can edgeguard Diddy pretty well. I think this MU is still a -1 for us, though, because as a character, Diddy is simply better than us. He doesn't exactly need a banana to beat us. His pressure, combo game, and kill power are pretty good, and his peanut gun isn't a bad projectile in its own right. Also, Diddy can use our top against us better than most.
: I'm not sure if this is that good MU for ROB. DK got a good neutral game as well as punish game.
