Help one sad Poro.
Find one mural.
Get all Trophies.
Win all the snowball fights against Willump.
Eat a bunch of berries offered by Willump.
Hug Willump.
Throw a snowball into Willump's open mouth!
Break a snow figure made by Willump.
Enchant an Elnük with the Flute.
Help all the sad poros.
Find all the yeti murals.
Find one stanza of the Notai Song.
Complete the Notai Song.
Activate 5 consecutive climb boosts.
Complete all sledding sequences without taking any damage.