Capture 20 Glittermoths
Glittermoths are a moth/butterfly you are required to capture during one of the main quests before facing the Hoof Puff world eater. They look like a butterfly inside an area of other shiny butterflies.
You acquire 5 for the main quest from a specific location, then they become the most annoying of the animals to farm because they don’t respawn at that location again or seem to have any other sort of set spawn location like other animals. They can spawn basically anywhere in the game world, so the only way to catch them is to just randomly come across them. Make sure to always grab them if you see them while wandering around during normal gameplay, because they are frustrating to try and farm for later.