Here is the full list of all 31 The Adventure Pals achievements. It takes around 10-12 hours to unlock all of the achievements on Windows.
You've used nine lives but don't give up
Beat an arena
Release 50 old people from hotdogs
kill 100 enemies by jumping on their heads
Make it to second island
Defeat treefist
Use a Weapon Mod
Collect 10 cupcakes
Kill an enemy that's been converted to a bunny
Use the Cupcake Converter
Complete your first objective
giraffe-copter for 5 minutes in total
Level up your abilities for the first time
Vanquish 10 enemies
Collect first cupcake
Get your first pal
start a co-op game
Kill 20 yaks on world map
Defeat Breakfast Buccaneer
Defeat Veggiesaur
Defeat Crab mech
Defeat Hot Dog Boss
complete a stage in less than 3 minutes
Give the whale the old mans underwear
Defeat all the arenas
Find 50% of the stickers
Fill up your sticker book
Get all achievements
Unlock all costumes
Fully Level Up
Finish the Game