Here's my anti Luigi guide and the one tip that changed my entire perception on the Luigi match up:
F-smash not only hits his fireballs, but the pikmin continue on to hit Luigi as well. And that goes for any color pikmin.
Luigis love to throw fireballs and then run up to grab. So whenever they try this, fsmash the fireball. The pikmin gets a slight pause in air when it hits the fireball, but it's not a clank. Hitting the fireball does not nullify the pikmin hitbox, meaning Luigi cannot ever run up to you after shooting a fireball. If they try to run up after the fsmash is over, just fsmash again! Gotta love Olimar.
Keep in mind that all Luigi wants to do is grab. That's his whole game. So fsmashes and pivot fsmash (as @
-The Gucci Fairy-
said) are your best weapons. If Luigi thinks he's going to be clever and just sit back and spam fireball, then throw a red pikmin at him. Not only do they cleanly go through fireballs, they also start eating the fireballs when stuck to Luigi. He'll probably try to throw out a few more fireballs before realizing there's a pikmin stuck to him, so you can run up and grab him. You can also try throwing a yellow at him since they arc nicely over the straight line that his fireballs travel.
More Luigi tips:
- Because you will have effectively shut out his options for running at you and because his aerial mobility is trash, he may start approaching from the air with a falling tornado. Everything clanks with tornado, so respect it. Just run away and fsmash, grab, or pivot option his end lag.
- When Luigi is trying to recover, throw a pikmin directly at his side-b. Pretty sure pikmin do *not* stop the down-b tornado, but they absolutely stuff the side-b.
- Luigi will often aim to side-b directly under the ledge. This is for two reasons - either he can directly up-b to snap to the ledge or he can tornado to rise up. When Luigi side-b's directly under the ledge, run off, hold down, and dair spike him. There's enough lag on the end of his side-b missile to make him never side-b under the stage again, which forces him to recover high.
- Luigi is very vulnerable during recovery. Once you've conditioned him to recover high, swat at him with fairs. Be careful for an active tornado, but both tornado and missile have end lag that make them vulnerable.
- When you dthrow -> fair Luigi, he will instinctively try to nair out of the combo. After the fair, you can fade back in the air just enough so that Luigi's nair will miss you, then fade back in to hit him with another fair over his nair kick. Only works when Luigis are so conditioned to just spam nair to get out of any combo, but you'd be surprised how much it does work. Basically you dthrow -> short hop and hold forward to fair -> hit Luigi -> immediately hold back in air to move Olimar's hurtbox out of range of the nair -> Luigi nairs -> hold forward to move back into range in the air -> fair his nair or his landing.