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