So Rob is a fun matchup. A very skilled Rob goes to a local venue near me, so I've gotten a bit of practice against top tier Rob.
Pros:
- GP, like in most of these matchups, matters. Being able to steal the top, and use it in conjunction with Luma gives Rosalina an incredible amount of stage presence. It's also important to GP the lasers near the ledge, otherwise risk losing Luma while shielding.
- Rob's recovery is fairly weak to persistent drawn out edgeguards, which is something Rosy can do well. I wouldn't recommend ever attempting to land a spike, as he can always pause his recovery to throw out a very persistent up air, and anything to knock him outwards is almost as lethal as knocking him downwards. Rob is on a very finite clock whenever he's off the stage, and reading an overly desperate attempt to return ( going high, using back air to move quicker, etc ) can lead to some safe kills.
- Most of Rob's aerial options are slow, so pressuring him in his weaker areas is very useful. His back, neutral, and down air all have a very noticeable pause that can be punished on reaction. I'd argue that being extremely aggressive against Rob is vital to beating him, as it allows you to punish these slow startups before their superior disjoint has a chance to play a part.
Cons:
- Most Robs prefer killing off the top, something Rosalina is quite weak to. His down throw to up air is quite difficult to get out of at mid percents, and his up throw outright kills after the 100 mark, allowing Rob to have very guaranteed kills if the stocks ever stall out. In addition, his up smash is a very potent anti-air, and his most powerful smash attack.
- Actually getting in on Rob to deal damage can be a hassle. Rosalina, while having a projectile nullifying move, is also incredibly tall, and easy to hit with projectiles. Her average aerial move speed, and fairly slow fall speed make chasing down fleeing opponents more difficult than it would be for other characters ( I'd recommend banning the longer stages, such as Duck Hunt ).
Overall, I feel like this is a matchup where the Rosalina is required to play quite aggressively, as doing damage from Melee is her only real option ( Sending Luma out is laughably bad, and using GP exclusively is only stalling the game, letting Rob's laser build up strength ). Spacing is key, as many of his moves are very difficult to challenge, and much better responded to during the startup, or end lag. It feels like getting offstage gimps are essential as well, because Rob has very easy kill options once Rosalina gets higher in percent, giving him the edge if both players are in Rage percent. It's a matchup that requires the Rosalina to use every tool in her kit well in order to succeed, but given two players of equal skill, it is certainly in her favor.
I'm going to go with 60:40 for Rosalina. I don't think it's anything worse than that, although a case could be made for it being even more in Rosalina's favor.