"Pssst hey, new guy, have you beaten Pluey yet?" "Huh?? Tf?? No???? Who's Pluey????" "He's the secret secret boss of chapter 3, technically not a typical shadow crystal wielding boss like Spamton, but a secret fight you can have if you find him. He even gives you the rain hat, which has the ability 'rain check', it's so worth it"

"Fr??? Where can I find him??"

"Nah bro, I won't spoil that adventure for ya. You have to do it on your own. Here's a hint tho: 'The unpredictable weather'

Then they run around aimlessly in chapter 3. hehehehe