Here's my Mario matchup chart. Most of this is through experience, and I made this by myself in like 2 minutes. Kill me for it, guys ¯\_(ツ)_/¯

Why Pikachu of all matchups as the worst one?

Because I feel like Mario losses in the neutral and plus Pikachu's priority is slightly ridiculous. Mario can't cape Thunder Jolt (if that's what it's called) and Pikachu's Thunder destroys Mario on stage, AND when Mario is above Pikachu.

But surely Lloyd or Marth is worse? Mario has a chance at edgeguarding (more than most characters can say), an OK punish game into decent kill moves, and a recovery that's pretty hard to edgeguard because you can Cape Thunder.

I think Mario vs Lloyd could be worse, and you can cape thunder? I did not know that. Anyway, Mario won't always have the reaction time to cape thunder offstage, which is why I think Mario gets wrecked. And not to mention Pikachu's Uair and Utilt beat a lot of Mario's aerial options.

Id rather see BM v Mario as 5-5 tbh

And I dont see Samus Mario as being that bad for samus

Pika is not that bad, but it is indeed stupid. Pika simply need to rely on reaction to slide-Utilt, mindgame neutral into surprise Smashes, work up to mid-damage to Dair/Nair you off-stage and just edgeguard. And if he's an Up-smash, he gets his silly for free Thunder-spike to a tech-chase Up-Smash and rinse repeat until you die. You really need to tech correctly, but in general, learn avoid being put into those Thunder situation to begin with.
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You as Mario still have control over neutral with fireballs and can clip his tail-hurtbox with wise positioning. Fireball camp wisely into damage setups and traps into smashes. It is a doable match-up: maybe 40-60, but not worse. It's not a terribad losing MU based on execution needed, but it does take smart thinking to keep it close to even. It only feels very frustrating because you know your opponent plays with the IQ of v***** discharge and somehow can be 3-stocks up if you don't pay attention.

Fox is probably Mario's worst MU. Despite being able to have good punishments on Fox's fast-speed, neutral is nearly impossible against a good Fox player. Everything he does simply defeats everything Mario attempts. Run-up Shine works on Mario for some reason too. An average Fox doesn't make it seem bad; a good one can just easily overwhelm you to the point where it doesn't even feel fair.

I don't honestly know if Mario truly wins many MU. Even if he does, he has to work pretty respectively for it. I think he only has some significant advantage over Wario and Ness. Every other mid/low-tier (Ichigo, Peach, Link, Yoshi, even Kirby) have some stupid things to punish him hard, force dangerous situations, or control neutral just as well, or better than him. It makes things too close to even for him to win.

At the same time: I think he surprisely goes even with many higher tiers like Sheik, Donkey, Meta-Knight, Naruto, Marth, and Black Mage. I think he feels bad in some MU's because he pretty much loses neutral in all of them, but still has one the highest average damage output in the game with some really strong and fast kills moves.

Mario has tons of weaknesses with no reliable jank. Up-Smash at best is just a good optional coverage to beat a mashing-out-of-hit-stun / stuck in a frame-trap opponents. And the mechanics of the game work against him more than other characters. This makes him very skill/experience required. He's probably the most "honest" character that needs good fundamentals to strive.

The thing with Fox is that he's sorta expected to win neutral against every character, but at least with Mario you get punishes with chained usmash and grabs that can do a lot of damage, and good edgeguarding. Not nearly as bad as Marth/Lloyd IMO.

Kind of late, but: Advance movement with Mario really makes his neutral go strong against Lloyd and Marth. He's still has to what off for there range, but can go still go head-to-head with them with offensive and rushdown. Marth is also perfect combo floatiness for Mario's aerial string. Not that bad as MUs. It's another case of having overall less/worse options, but still have the options that keep it a manageable close MU.

Against Fox, he doesn't just have better options than you, but the ability to deny the usefulness of the good options you have left. And his speed neutral really makes it difficult punish him effectively. He punishes Mario twice as hard, with half as much effort. It not Mario can't punish Fox very hard, but you have to be unrealistically perfect with the execution of your punishes to keep the MU close. You can't afford to make even one drop; in the long-run; it could definitely cost you the match. You could be punished for every mistake, even the smallest one; but Fox isn't as vulnerable in the same matter.

fox is definitely not mario's worst. neutral is actually decent with dash attack and utilt being able to stuff fox's moves. nair is good as always.
fireball's really bad in this MU imo, so if you rely on that for other matchups I can see why you think fox is unwinnable.
also you can actually punish fox consistently unlike 90% of the cast.
fox is like 60-40 fox's favour imo. about as bad as marth, maybe a little harder.

other than that pika probably isn't 65-35, never particularly struggled with it.
zelda is mario's worst MU imo, completely shuts you out in neutral and kills/edgeguards very easily.
DK definitely beats mario at least 55-45. killing him is f*** ridiculous.

other than that I agree with zalo when he says that mario doesn't really beat anyone, especially harder than 55-45.
his moves, while solid, aren't particularly effective against any one character, and are instead mediocre against most of the cast.
maybe you could argue a 55-45 vs. puff/kirby but I'd hesitate even there tbh.

. Nah. Nair can be anti-air'd by even Fox's Jab. Dash-Attack and Utilt stop working when an experience Fox (Aegis, Tai) understands the use of those tool. Fox's Utilt beats all three of those moves; when he's in doubt about about what move you'll throw out next (or the timing of your approach, Slide-Utilt, and Fox will win the challenge almost everytime into a follow-up situation: Shine-Utilt is also a strong alternative.

With those tools minimized in use, you're only left with risky tactics like baits into tornado/Usmash, fireball-spam, or pray for a mistimed approach when you do a RAR-Bair. But those too get snuffed out by Fox's RAR-Bair or Sliding-Shine Bair. So without a Fair approach, you have to get heavy punishes anytime you do get a confirm, because you'll have to lose another 5-10 exchanges before you get the chance again.

Marth isn't that bad. He's perfect combo weight for Mario. One of the few characters Mario can very consistently do other aerials in Fair. Marth's also very vulnerable to setups to Tornado off the top too. It's more 55-45, but I really do think I could clean it up to 50-50. I feel like I don't use Bair enough for edgeguards and Marth pretty much dieds once he gets clipped without a mid-air jump.
The Zelda-main in me agree's it's in advantage her. But the Mario-main in me says it's not that bad. I still feel like staying right outside of Zelda's attack range and forcing her to commit to approaching is still a big apart of fighting her when you have the mobility advantage. Because you can still react to all of her options to cover the farther ranges; Din's, SH-Nayru, Teleport Mix-Up, they're pretty slow. It's a difficult MU to decide because no Zelda plays the MU right and all end up turning to Sheik/switching to a fast-character next match once their down against my Mario (which is a better MU for him), but she's still less worse to fight than Fox.

Here's the thing about Zelda: she doesn't have to approach, and she won't. Just being outside of her range isn't pressure unless you can hit her, which Mario can't. Zelda can just use her safe moves (Lightning Kicks, jab in some situations, etc.), mixup approaches with dash attack, Nayru, and Din's, and as long as she powershields or Nayru's your fireballs she has nothing to fear.

You don't have to approach her either. It's not about fireballs or zoning, it's just assertng your superior mobility over her. You can still run and move in-and-out of spacing faster than she can. Against an opponent aware of here physical-range, she can't reached opponent quick enough in many situations without some from of commitment with approaching on her part. From Din's, to Short-Hop Nayru approach, Short-Hop Fair/Nair, to Dash-Attack; they are still reactable at a mid-range distance.

Facing Zelda in neutral isn't the hardest part about fighting her when you have a faster character: the hardest part in almost any match-up is her kill power. She only has to land a quarter as many moves as her opponent to take a stock, so even if she consistently does lose neutral 10 times to someone who know how to overwhelm her, she only has to win neutral 2-3 times for the advantage.

being faster =/= winning neutral
sure you can run around but the fact is she has giant f*** feet and will just kick you whenever you come close.
and mario might be faster, but not fast enough to dashdance grab zelda kicks before shes actionable

think fox zelda but instead fox is complete s***.
please tell me how mario does ok in this.

the first 2 zelda approaches are basically gimmicks so I dont think they're really good against any character tbh
the SH aerials are the problem - even if they're "reactable" why does that even matter lol, marths aerials are "reactable"
all you have to do is gradually limit mario's space and options using ur giant hitboxes and eventually you'll get close enough to f*** him.

and of course theres also the fact that she punishes 100x harder than mario does but that goes without saying