Here is the full list of all 60 Legend of Grimrock 2 achievements.
Complete the game with old school mode
Complete the game with Ironman and Single-use Crystals modes turned on
Reach level 10 with a farmer
Summon the Viper Roots in under 6 minutes
Find the Relic
Polymorph 10 times
Find all secrets
Enter the Nexus
Mix a total of 50 potions
Visit all levels
Enter the Shrine of Balance
Complete the game with hard difficulty setting
Defeat the Lindworm
Collect and wear archmage's uniform (4 pieces)
Catch 25 fish
Dig up all treasure chests
Collect and wear full set of Meteor armor (6 pieces)
Defeat a Magma Golem
Find the pie
Enter the Pyramid of Umas
Enter the Castle
Collect four elemental essences
Defeat the Wormbound brothers
Collect and wear full set of Crystal armor (6 pieces)
Find Bane
Perform 500 missile or throwing weapon attacks
Find 8 skulls
Open the gate to the Cemetery
Assemble the Meteor Hammer
Collect and wear rogue's wardrobe (5 pieces)
Perform 100 power attacks
Cast 500 spells
Find 50 secrets
Enter the Crystal Mines
Kill 250 monsters
Defeat the Ratling Boss
Kill a monster by throwing pants at it
Learn 15 spells
Defeat a monster with a backstab attack
Open the door to the Archives
Open 5 gold locks
Defeat the Summon Stones
Mix a total of 10 potions
Kill a monster by teleporting on it
Travel 10000 tiles
Kill a monster with a single blow
Find 25 secrets
Max out three skills
Dive 250 tiles
Cast 250 Spells
Visit 10 levels
Max out a skill
Defeat Herder's Den
Collect an elemental essence
Dig up three treasure chests
Perform 500 melee weapon attacks
Find 10 secrets
Defeat the Viper Roots
Cast 25 spells
Deal a killing blow with unarmed attack