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