Here is the full list of all 15 FOX n FORESTS achievements.
Loot 10 treasure chests.
Do a Patty Launch.
Defeat 3 enemies with a Stomp Attack.
Finish a stage without defeating a single enemy.
Gather 9.999 coins.
Upgrade your Mana Bar to the maximum.
Buy all moves.
Upgrade your Bayonet to the maximum.
Buy all hearts.
Find all (4) empty bottles in the game.
Finish all (4) Bonus Levels.
Finish a level without getting hurt.
Finish the game.
Finish a boss without using help.
Finish the game without using a single potion.