Here is the full list of all 27 The Knight Witch achievements.
Use 10 Spellcards in 10 seconds
Find Pistola and bring him to the Castle
Find Pistola’s lost courage
Have more than 15 mana at once
Slash a stunned enemy with your sword
Obtain 1 Frost Moon
Obtain 27 Frost Moons
Obtain 1 Radiant Sun
Obtain 27 Radiant Suns
Amass 10,000 shards
Get 10 cards from Lord Yupi
Try 8 different types of armour
Get every Link upgrade
Defeat 1,000 enemies
Save Kalypso
Let others take care of the problem
Defeat the Hextinction
Master Akai's shooting range
Break 100 destructibles
Find the hidden old ship wreckage
Defeat 100 enemies without using instinct aim
Save 14 prisoners
Find 6 Growth Seeds
Infuse 20 Arcane Beacons
Defeat 5 Loot Golems
Complete the mission at the Mirror Lake
Activate a cheat