Hi Marth players! Pit player here to fill you on in on how I think this matchup goes!
Just to state for the record, I used to play this matchup near-daily for months, but I haven't played as much since. I may be a tiny bit rusty on the specifics in that sense, but I think I remember the fundamentals of it pretty well.
This is a tricky matchup for Pit, since his optimal range (mid-range, spaced with aerials and aiming for the sweetspot tipper) is Marth's optimal range, right down to the sweetspot on their blades' tip - trick is, Marth gets way more benefit from playing to his optimal range than Pit does. Marth is also very quick on the draw and his moves come and go quickly compared to Pit's, so he can pressure Pit very well if he can get in. Pit can keep him out with f-tilt and retreating f-air or reverse b-air, but besides that, Marth can challenge Pit's moves in the air with his disjoints (Pit's n-air and u-air are particularly unsafe if Marth comes in from the side). Marth's shorthop n-air is a good way to cover space and pressure him if you're right next to him, with sufficient speed to make Pit respect it instead of trying to challenge it, since the best way we can react is to shield into grab or jab. The constant threat of whiffing a move and eating a tipper f-smash to the face can distance Pit from the neutral game. This means Pit will try to move out of his optimal range and force you to approach, spacing with fullhop arrows, f-tilt, retreating f-air and shorthop d-air as necessary. The transcendent nature of Dancing Blade makes it a good answer to Pit's air game, especially forward Blade if he tries to retreat or upward Blade if he goes for an overhead hit. The catch is that, if you play too violently to get in - especially with f-air - Pit will shield-grab and get you into the air. While I think Marth wins the neutral game, Pit can make the match miserable if he gets you into disadvantage.
If Pit gets to in the air above him, don't try to force him to back off. Pit's u-air can juggle for days and, depending on how you DI, he can followup with f-air or b-air, or even d-air (which combos into itself) for extra damage. Best bet is to just go for the edge of the stage and try to force a reset. This goes without saying, but it's important that you try to minimise Pit's ability to get you into disadvantage, because while we don't have terrific combos, we can followup and pressure you back enough to get some good damage in before you reset. Especially if you're at high percents, try to avoid getting forced to the corner: Pit's f-throw will kill Marth at about 150% with a bit of rage if it's fresh. Grab evasion is key in this matchup, especially since our d-throw is a combo throw and f-throw kills. Just be careful of spotdodging too much, since our gentleman jab is great for catching the spotdodge.
I think Pit has the better disadvantage state. We don't have to worry so much about getting knocked into the air or pushed to the corner, because we can just try to go for the edge to reset and we have Upperdash Arm as a Hail Mary in case we just want to break your combo (this has the extra advantage of getting you into the air, which is good for us). Don't underestimate our ability to just go right off-stage and snipe you with arrows or try to force reset: we don't have much to worry about off-stage, and if we want to play coy, we can just fullhop arrow to force the approach. You will eventually have to come to us, so we can just play it cool and bait a move if we have room to breathe.
Off-stage, Pit excels. We can chase you off the blastzone with f-air strings and d-air's frame data means it's pretty risk-free. We can even gimp the recovery options with arrows or weave about to make it difficult for you to get back. We don't have to worry too much about being edgeguarding ourselves, since we can go deep to evade you and recover without too much difficulty from below the stage with up-b or in from the side with side-b. Disadvantage remains decent for Pit in this context, difficult for Marth.
Platforms can be fun in this matchup. We don't want to stay above you because u-tilt and u-smash can be deadly, you don't want to stay above us because u-air can juggle and u-smash can end the stock at mid-high percents. We
will try to shark you if we can, so be careful of taking us to stages like Battlefield and Isle Delfino where we can get the chance to do so. I think Final Destination is a decent stage for Marth, because it minimises the chance that Pit can do dirty tricks with arrow shots and it's easier to reset from a juggle situation; if it's possible, try to go to Duck Hunt, since it has the essential structure of Final D with the extra benefit of the ducks, which can interrupt the arrow tricks.
Counter is pretty weak in this matchup, for reasons a friend (a former Marth, now Roy, player) calls the "Meta Knight Effect". In other words, Pit's moves tend to be multi-hit or don't have the necessary damage output to warrant Counter being a viable tactic, since the first hit will be countered to do very tiny damage. That and we can just grab you out of it or read it for f-smash. I don't think Marth really makes too much use of Counter except with a hard read, but it's good to bear that in mind!
In short, Marth wins the neutral and advantage, but has a relatively weak disadvantage. Played optimally and spaced well in neutral, Marth's footsies and tipper can serve to make this quite the tricky fight, so I think the matchup is fundamentally good for Marth and poor for Pit.
Disclaimer: everything I said works the same for Lucina, but the distinction between Marth's tipper and her neutral damage output means Pit can be more at ease in the matchup.
55:45
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