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