I've tried and searched for so long on how to tackle those two achievements but I always turn up blank. Any help would be appreciated, thank you so much!

Hey, i just figured this one out.
Right click a gloomper with one of the music disks in hand.
I won't tell you which one though.

This is not the place to be asking questions, this is the issues tracker for the mod specifically for bugs and enhancements. Do not use this for random questions, please; join our Discord instead. https://discord.gg/zrnMPDM