spaces like nobody's business
quick 4-hit combo with the dancing blade without much vulnerability if you input the right combo or cancel mid-move.
Great Throws and combos.
good spike with dair if tipped
Fair and Nair are fast and combo easily
D-tilt edgeguards well
Smashes are fairly strong if tippered.
Counter is great when timed properly- which is hard to do
Fast dash makes for great dash dances into dash attacks.
mindgames like a boss
Combos are easy and hard to run from.
Tippers- hurt like all hell if you land em.
dtilt shield pokes
u-throw puts opponents in a vulnerable spot
d-throw gives combo opportunities
Dolphin Slash's sweetspot is right at the beginning of the move so get right above the opponent when you use it.
Dancing Blade's got a meteor smash if the second hit is up.
U-smash has a pretty large area, covering a large area around Marth's legs and his entire sword. As usual, greatest damage is at the tip of the blade.
Counter is easily punished with grabs so use it unfrequently
Dolphin slash has bad horizontal reach and easily punished so a substandard recovery.
susceptible to projectiles
he cant rack up damage without tipping.
Bad matchups vs top tiers characters
Dsmash is laggy
Dancing blade has lag depending on input
Marth's worst matchup is vs sheik, and he doesn't do well vs space animals, Ganondorf, and Young Link, but is excellent vs most others. Versus Sheik, the trick is to shield against her needles and use marth's quick dodges to capitalize on Sheik's vulnerabilities, like after smashes and her side special. Space animals are easy to deal with, as Marth's chain throwing abilities are excellent and he can easily close distance. Against Ganondorf, use speedy combos like Dancing Blade and Marth's dodges to capitalize on Ganondorf's slow speed and laggy attacks. Young Link is really just a clone of Link, so watch out for bombs and try to get close where projectiles are less useful. General strategies for Marth are: Dominate the air, keep the opponent overconfident, use Marth's speed to dizzy opponents. Marth's play style requires a lot of smarts and strategy, as well as deception. to quote Sun Tzu; "All warfare is deception". Keep that in mind as you use Marth.
Here's a scenario: Marth vs Falcon, Final Destination. marth is at 20%, Falcon at 10%. marth is standing at the center of the stage, Falcon is in the air up and left of Marth. Marth jumps up, Falcon uses the knee, but Marth pulls out a quick counter. Falcon DI's and lands at the left edge of the stage. Falcon runs towards Marth, who maintains center. Instead of using a dash attack, which would leave Falcon open, Falcon dodges backwards to avoid Marth's improperly timed f-smash. Falcon knocks Marth into the air with raptor boost: Here Falcon has a choice: use Falcon Dive, or an aerial. Falcon, impatient to get the stock, decides to go with a n-air. This is mistimed, as Marth midair jumps and uses Dolphin Slash directly above Falcon to get the greatest damage. Falcon DI's, runs to where Marth has landed, and grabs him, up throwing him and following with up air. Marth Takes the u-air, but when Falcon goes for the Knee again, a quick Counter sends him flying. Marth dashes forward, but dodges behind Falcon, back throws him, and follows it up with a Ken Combo for the KO.
U-throw to u-air
f-throw to uncharged f-smash (only on low percentages)
Fair to fair, tilts, throws.
Dtilt to fair, ditilt.
Ken Combo- most famous marth combo-fair string-dair
these are just a few ways to improve your skills as Marth.
Shoutouts to @dude it's raining for the advice.