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