Here is the full list of all 47 Gift of Parthax achievements.
Complete entire game using only fire as primary element
Complete the entire game without a single death
Gain light magic
Damage more than 5 enemies with the effect of an explosive rune
Adding 4 of same kind of rune to a spell, first time
Read the introduction story
Died 10 times
Transform 10 enemies into chickens
Complete a challenge with only Arcane spells equiped
Complete a challenge with only frost spells equiped
Complete a challenge with only earth spells equiped
Complete a challenge with only fire spells equiped
After Parthax' death
Complete blood moon season
Defeat Parthax
Purchase all runes available
Defeat 1000 enemies
Gain blood magic
Complete winter season
Defeat Hrist
Collect 99 mana potions
Collect 20.000 gold
Collect 50 mana potions
Collect 10 mana potions
Collect 99 health potions
Complete fall season
Defeat Nereus
Died 3 times
Defeat 500 enemies
Find all objects for a season
Open an empty chest
Complete summer season
Defeat Feykir
Collect 10.000 gold
Open a chest with riches
Destroy all breakable objects for a season
Collect 50 health potions
Collect 10 health potions
Collect 5.000 gold
Complete spring season
Defeat Mounorian
First death
Defeat 100 enemies
Collect 2.000 gold
Purchasing first rune
Complete the tutorial
Casting first ally spell