@ Golden Leeroy: You also 3 stocked my Marth on Yoshi's Story with the same pink luigi so I guess those cancel each other out. Seriously, do you have any tips for me on how to NOT get 3-stocked by a Luigi?
I play his luigi like all the time with marth, so I'll try to help you out if I can.
For one: try your best to read the WDs. Luigi slides around like a ************ and hearing the "JA JA JA JA JA JA JA JA JA JA JA JA JA JA" continuously isn't going to do your concentration any favors. What you need to know is that if you don't play too aggressive, eventually Luigi will come to you, and there his options are limited enough for it to be a guessing game. Your range does help you out a bit in this guessing game because even if you guess wrong, you might get bailed out by the long sword
Don't try to fair combo him unless you know for sure you have the tipper. Sex kicks can bail luigi out of fair chains if the spacing isn't perfect, because that move is just that broken and just that quick to come out.
Do whatever you can to avoid the ****ing tornado on the stage, preferably punish it so that your opponent is more reluctant to use it. It deals surprisingly good damage and can be used to start combos.
You have practically no grab game unless you get lucky and he uses his second jump for whatever reason. Luigi just floats too far and his aerials come out too fast.
Always expect another aerial to come out. Luigi's aerials have like no lag whatsoever. If you make him miss once and jump in to try and take advantage, BOOM, you just got pimp-slapped by the fair.
Tilts are your friends, especially utilt when luigi approaches by air. Not to mention it's harder to punish an ftilt you threw to try and catch a careless WD than that fsmash you might've thrown...
Edgeguarding is one of the easier tasks of this matchup in my opinion. You always have to be wary of a potential misfire, but luigi's options are rather limited. if he's going to get back, force him to land the missile on the stage. So long as he doesn't hit you, the lag is so great you get a free fsmash tipper. If he's not at a decent height, I'd suggest hanging on the edge as if going for the edgehog, drop to the correct height at the right moment, and then rising bair before a quick recovery to the stage. Also if you can time it right, jumping out with a shieldbreaker can usually do you some good. If you're staying on the stage, dtilt to keep him away from the ledge. Remember the tornado will only rise once during a recovery. Afterwards, it cannot gain vertical distance unless Luigi gets back to the stage. If the tornado is used, remember the options are just that much more limited. It'd also be good to note that if Luigi does grab the edge and he ledgehops, remember he can get off two aerials before he gets to the ground. Overall, i think the best option is to smack him right when he starts charging a missile (assuming you chased him off the stage). Just don't go so far out you risk dying yourself.
Use platforms to land an nair or something if they have to techroll.
Try not to get grabbed. Even if you aren't a fast faller, Luigi can still do some stuff to you out of the grab game.
In all, I find it's better to play this one on the defensive. I dunno, but that's pretty much all I think about when I play his luigi with marth. I'd say we split the matches 50-50, but this stuff usually at least keeps me in it to even make big comebacks or whatever. The big problem is that not a lot of people play against luigi often, so they have no idea what to do.