Here is the full list of all 37 Ori and the Will of the Wisps achievements worth 1,000 gamerscore.
Completed Hard Mode
Beat the Game Without Spending any Spirit Light
Beat the Game Without Equipping a Shard
Completed the Game in Under 4 Hours
Completed the Game without Dying
Completed the Game
Maxed out Life
Completed all Spirit Trials
Defeated Shriek
Completed all Wellspring Glades Projects
Completed every Side Quest
Found all Collectibles
Defeated the Willow Stone
Unlocked all Abilities
Bought all Maps from Lupo
Maxed out Energy
Completed the Trade Sequence Quest
Escaped from the Ruins
Unlocked all Shards
Upgraded all Shards
Upgraded all Shard Slots
Completed all Spirit Shrines
Defeated Mora Without Taking any Damage
Fended off Mora
Defeated 3 Enemies with a Single Spike
Upgraded all Abilities
Escaped the Avalanche
Fended off Kwolok
Defeated Kwolok in Under 2 Minutes
Defeated 5 Enemies Without Touching the Ground
Juggled 3 or More Projectiles in the Air for Over 5 Seconds
Defeated 10 Enemies using Environmental Hazards
Avoided Touching any Corrupted Water
Cleared the Watermill
Reached the Wellspring Glades
Defeated the Horn Beetle
Fended off Howl