Here is the full list of all 37 Aritana and the Harpy's Feather achievements.
Stay in the air for one minute without hitting the ground.
Make 3 different combos without hitting the ground.
Make 100% of the game and see the extended ending.
Survive the third encounter without using the Defense Ability.
Get all Muiraquitãs.
Get all the Mountain Muiraquitãs.
Find all combos.
Survive the second encounter without letting any rock hit the ground.
Jump a great distance using the Agility Boost.
Lose 3 lifes against Mapinguari in any encounter.
Reach 99 lives.
Make a combo using the Strenght Boost.
Lose one health point trying to attack a Red Spirit.
Survive the first encounter without losing health.
Get all the Cave Muiraquitãs.
Get all the Forest Muiraquitãs.
Win the Mountain battle against Mapinguari.
Find 3 combos throughout the game.
Complete all the bonus stages.
Reach maximum health.
Get thirty Muiraquitãs.
Win the Cave battle against Mapinguari.
Dodge a Red Spirit and make him fall into the abyss.
Get hit by a Spirit right after it's respawn.
Get fifteen Muiraquitãs.
Use the Search Ability to find a secret area.
Win the Forest battle against Mapinguari.
Collect 2 Medicial Plants to increase your health.
Fall 3 times into the water during the same level.
Lose one life in any level.
Bring down a tree.
Try to knock out a Spirit jumping over its head.
Offer five Muiraquitãs at the end of any level.
Make a combo.
Get 100 guaranás.
Get one Muiraquitã.
Avoid getting stunned after a high fall using the Agility Stance.