Here is the full list of all 13 Chop Goblins achievements. It takes around 2-3 hours to unlock all of the achievements on Windows.
Die on Sightseeing Mode
Find a lore-unfriendly secret in Greece
Complete Streets using only the flintlock and dagger
Complete the museum without taking any damage
Complete the museum level using only the dagger
Find a secret Impaler before Dracula's Castle
Beat the game
Get the wand at the end of Greece
Click one of the social links on the main menu
Find a hidden weapon upgrade
Kill an enemy with their own projectile
Beat the game on "Once Again" mode
Beat the game on "Goblin" difficulty