Grubfriend

Rescue half of Hallownest's 46 Grubs (so 23). Grubs are trapped in glass jars all over the map - smash a jar and the grub scuttles home to the Grubfather in the Forgotten Crossroads, who rewards you (geo, then charms and items) as your count climbs. Just break every jar you come across. See Metamorphosis for the full set.