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