sorry this is so late but I Juuuuust noticed this.
Let's talk ROB!
I play mainly Marth but the match ups are so darn similar it's worth talking about. I've probably played this match up more than any other Marth in the world against good robs.
When playing against rob there are two things you MUST keep in mind,
1. Gyro placement, know how charged it is, or where it is at at all times. ROB's laser isn't that big of a deal and you can punish him pretty easily for it if he uses it too close, and too close is about 2-3 sword lengths away. So back to gyro, a smart rob will use his gyro to get grabs off of you, he will also keep you on or near the leadge with gyro throws, I've had upwards of 40% racked on me from one gyro in smash 4... Gyro is insanely good. Other janky gyro things: If ROB has gyro in hand and you are own ledge, you need not to ledge roll, or HE WILL throw the gyro down on the stage and you will get spiked to oblivion. If he spaces the spin well we'll create a situation where it can become very difficult to approach without getting hit by hard read smash attack or a grab, both are obviously bad. which leads to point 2 on what to avoid, RoB's silly grab game!
2. RoB's grab game is pretty good in this game and nets him reliable kos. while it's not as bad as it once was... (thanks to up throw nerfs) it's still pretty bad, at high percents if he throws you with dtrhow, simply jump away, be weary though if he tosses you up at 70% he may just ko you with the up air that follows. if customs are on robs d-throw becomes a 50/50 guessing game at pretty much any percent due to his enhanced jet booster.
So marth/lucina's objective on this match up is fairly simple, get ROB either off the stage or above you. Bair beats EVERY Aerial he has, no question, if you space it properly bair beats out robs nair every time, if you play marth, due to the spacing that bair requires to out space nair it will always tip. Up air will also beat nair if spaced properly. Pretty much all of marths aerials wreck rob if you space them really tight. If you are reckless however you will eat every nair he throws out while trying to get aerials... spacing, spacing, spacing. If you see him flub out really bad land a sour fair on him (if marth) this will lead into up air or fair, abuse this.
If Rob is off stage and recovering, he must use one his aerials in order to spot dodge, remember this well as this is where you will rob most of the time, I've lost track of how many robs i've forced into a no fuel to death situation since he has such a hard time getting back. If he is in jet boost, jump at him swat at him, the worst he can do is try to throw out an aerial back, and remember all of our aerials beat his, as long as we're not challenging his up air with our dair, but for bonus points, if rob is recovering full vertical to the ledge, simply drop down and feign a dair, wait til he throws the up air out then spike him. He'll recover back but often in a panic at that point, dolphin slash him to kill him after that. Speaking of dolphin slash if he is under the stage you get repeated stage spikes on rob, hope rob is good at teching! Most RoB's however won't recover down like that.
ROB does nasty stuff to marth in the air too though, it can be very hard to land against a rob that knows whats up, also he ledge guards and ledge traps marth really well due to gyro.
This whole match up is about getting rob in the air or off the stage, problem is, is that he's fairly good at staying on the ground and has really fast frame data, such as a dtilt that comes out on frame 3 (wtf) a jab that he can use to get grabs off of (also comes out stupid fast.) and a pretty damn good gimp game. Dthrow is your friend as marth/lucy in this game as it sets up our trap game fairly well. Also blue dancing blades, abuse them hard. Regardless though RoB stays on the stage slightly better than we are capable of launching them off it (not by much) the problem lies in how hard rob punishes us for our mistakes as opposed to the way we punish him. ROB simply kills us easier, that is unless rob screws the pooch hard and runs head lon into a tipper or gets shield broken (don't be afraid to use short hop shield breaker into a shield happy anything btw)
ROB wins either 60/40 or 65/35. Not sure yet.