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