Here is the full list of all 22 Lil Gator Game achievements. It takes around 3-4 hours to unlock all of the achievements on Windows.
Break everything on the island.
Craft every item.
Make friends with everyone on the island.
Take a seat in the Junk Shop.
Complete the story.
Equip the full ninja set.
Equip the full space set.
Swing with the Sticky Hand 5 times without touching the ground.
Equip the full paint set.
Try to touch the sky.
Completed Avery's Quest
Climb to the tippy top of the antenna.
YOU WILL NEVER KNOW THE TRUTH.
Learn the monkey's TRUE name.
Instruct the monkey on the power of creativity.
Learn the monkey's real name.
Learn the monkey's name.
Completed Jill's Quest
Acquire all bracelets, and gain enlightenment.
Completed Martin's Quest
Ragdoll into something as fast as you can.
Undertake a new, bigger quest.