Is there any way to deal with an Olimar who just keeps on throwing his Pikmin like his life depended on it?
You have a few options.
I don't know who you play, but...
- If you can play Fox, Falco, or Wolf, pick him, use down+B, profit.
- If you can play Marth or Ike, pick him, do normal stuff and use down+B a lot, profit.
- If you can play Zelda, pick her, use neutral+B, profit (or just use ftilt a ton). Sheik's chain used to be ok at stopping this, but not any more.
- If you can play Jiggs or Kirby, you can jump way over them and/or duck a lot. Then your nair can hit them off pretty easily, or down+b with Kirby (while it works to do that with Jiggs, I don't recommend it... unless maybe you just star KO'd Olimar...)
General advice:
- Any moves that quickly cover a lot of your body are good (Pikachu's bair, Kirby's nair, Jigglypuff's nair, Mario's nair/bair, and Link's nair are some examples), since you want to knock them off you when they get on.
- You should be trying to approach through the wall of Pikmin if you have no projectiles [and possibly even when you do], but if you think you can outcamp them (perhaps as Pit, Toon Link, or Link), running away while throwing/shooting stuff might not be a bad strategy.
- If you get a grab while Pikmin are on you, you can try to pummel to knock them off - may not work but it can stop them from interrupting the throw animation if it does.
- You should usually DI pikmin explosions onstage if you are offstage - the white ones meteor smash, so if you can survive those by being hit onstage (if, say, Olimar latches two onto you then starts comboing you and they go off), it's generally safer. Olimar will be looking to punish this though, so be careful (since it may occasionally be better to just try to meteor cancel it).
If you need more, I can think of more, but at this point, it's what I've got.