In the progression tab, under the acheivement, we should include skin completion, an way to know how many skin there is and how many they are unlocked, no idea for an possible reward maybe exclusive skins
Like at 10 skin an exclusive set or idk
#Skin progression
sly scaffold
dark mountain
Exclusive sets for a certain amount of skins sounds really engaging actually. It can also be like this: get all skins of some theme and get an exclusive set.