Here is the full list of all 25 Poi achievements. It takes around 12-15 hours to unlock all of the achievements on Windows.
Discover ALL the Locations.
Find ALL the Fossils.
Find the legendary treasure.
Meet the requirements to open the Mysterious Gate.
Collect all the Explorer Medallions in Crystal Cavern.
Collect all the Explorer Medallions in Sinking Sands.
Collect all the Explorer Medallions in Mount Magma.
Take a picture of the Master Explorer.
Collect 10 Explorer Medallions.
Find a hidden hat.
Collect all the Explorer Medallions in Cozy Canyon.
Do a triple jump.
Sometimes, things don't always go as planned.
Discover the mysterious travelling merchant.
Kick a Bucket Head.
Purchase an item from the shop.
Hey, watch where you're rolling!
Earn your first Explorer Medallion.
Beat the game in New Game+ mode.
Collect ALL the Explorer Medallions.
Find all of the hidden costumes.
Visit the hidden planet.
Rescue all the baby Pin Birds.
Find ALL the Golden Gears.
Take a picture of ALL the creatures.