the only hope samus has against marth is punishing him. this implies that a marth NEEDS to mess up, or else samus is screwed. her only hope is a charged shot, but a consistent marth won't let even the best samus charge. the only solution is to momentarily charge your shot between attacks/approaches until you fully charge it.
I completely agree with this statement.
There are 2 different kinds of Marths I've played:
-Those that like to Grab/ Foward Smash/ Dash Attack
-Those that like to spam Aerials/ Tilts
The former is what makes Samus players like myself smile, as you can bait them out to do the laggy F-Smash or Up+B their persistent grab attempts. This is what I'd refer to as 2001-2006 era Marth.
Note: Now of course a good Marth won't spam F-Smash blatantly and knows how to use their aerials/tilts as well, but even good Marths can't help but be tempted when their spaced perfectly for a Tipper. Basically, you can pretty much sense when a Marth is in range for a forward smash and counter accordingly.
The latter is what made me realize that the match is probably the Samus' most technically "impossible" matchup. That is, if you had 2 frame perfect AI players using Samus and Marth, Marth would always win.
Why? Because Marth's tilts and aerials destroy every aspect of Samus' playstyle. To defeat Marth you have to get into the mind of the player, not trying to probe for technical advantages too much.
None of your tilts or aerials are safe against Marth are safe, NONE- even when perfectly spaced. So you have to either prey on their ignorance if they don't know this, or pray for openings in their defense if they do. (Heck, even Charge Shot can be beaten by a clean Forward Smash. =/ )
And once you get in past mid range, you're now in grab range, another hurdle. Smart Marths will only dash JC grab, because they know full well that Samus can't wait to Screw Attack if they're both shielding and stationary. In M2K vs HugS, you'll notice how M2K did retreating Fairs away from any pressure situation, and Samus simply doesn't have an answer to that.
Against these tilt happy semi-defensive Marths, I've caught on to a few things:
-They have the timing for destroying Power Missiles down pat. Power Missiles may be a decent distraction to setup for things, but it won't really stop a Marth from closing in. The lag experienced from a Missile and a clashing Fair is negligible, so you can't rely on that collision delay to do much if they're SHFFLin' like mad.
What does work are un-charged or semi-charged shots, and random homing missiles. Marth players simply don't have the timing for these down and they often stumble trying to deal with them. Un-charged shots are wonderful because the hitboxes are deceptively small and will often go through their tilt attempts or scare them to shield. Even better, semi-charged shots add a little stun and they will often DI it poorly, allowing you to set up on them with a grapple or whatever.
Homing missiles do the same thing, and although can be easily destroyed, when used in tandem with charge shot can often distract Marths enough to force errors. They obviously work well in edgeguarding too.
-If a Marth is above you descending Uairs are a nice tool deal with their advance, and it can set up combos or grabs. The worst that can happen is you getting Dair'd, which you couldn't really stop anyway.
-Like DJ Nintendo said situational grapples, though highly risky depending on %, are pretty much necessary if you want to get some kind of damage on a Marth. What makes the match tolerable is the fact that Marth can be pretty much comboed or chased fairly easily by Samus, especially from a grab. I find mixing it up between JC Standing Grapples and Dash Grapples useful in throwing off their timing.
-Retreat! Knowing when to retreat is important, because Marth can turn the pressure back on you in a flash, all he needs is one Fair and you're now his play toy. Sometimes I like to get greedy if I get a weak Nair hit and try to follow it up with 2 or 3 more. But if a Marth is DIing properly he can easily do a mid-combo Fair and turn the tables back on you. (most likely you'll be DIing towards him to follow up, which gives him an easy combo opportunity as well)
I notice when you act really aggressive and back off, Marth players get frustrated and start chasing you down... which leads them to do risky stuff that you can take advantage of. So if I get a dash attack, and I follow it up with say, an Uair, instead of trying to double jump and chase them again- possibly getting Fair'd in the face, I fast-fall or waveland back and throw out a missile. Marth will either do a defensive Fair/Counter or Double jump, which you can intercept with a Charge Shot or w/e.
Following up aggressively is obviously essential in some cases to get a kill, but forcing it can backfire badly.