What is the best way to fight characters that can kill pikmin easily?

[MERPIS]

Even slower characters like ganondorf or Bowser, I throw my pikmin at them and they just do a lagless or fast move and it either kills it/them or shakes it/them off, leaving me to abuse my grab since throwing the pikmin isn't helping much.
On a side note, when is the best time to use side b over anything else?

 

[Myran]

If they're hitting your Pikmin its giving them extra lag, use that time to punish them. Also have them kill your Pikmin to get purples faster and allow for more pressure.

 

[MERPIS]

If they're hitting your Pikmin its giving them extra lag, use that time to punish them. Also have them kill your Pikmin to get purples faster and allow for more pressure.

what should I punish with

 

[Myran]

That depends on what move they use and what character, it can range from an aerial to a smash, grab, or side-b. I'd recommend watching some other Olimars to get an idea.

 

[Whamoth]

If the opponent's character is effective at killing pikmin use that to your advantage by always throwing pikmin you dont want in your line up like white pikmin and yellows and get the 1 or 2 percent before they are killed and get your lineup that way.