The game comes together very well, combining into a whole, very enjoyable, experience. Art design, animations and art itself is very good and, most importantly, consistent throughout. Music matches the gameplay well and sfx pops (in a good way). Main mechanic of using the spells is satisfying and different spells are unique enough not to be interchangeable.
My main criticism would be a lack of different enemies, some of which would necessitate player's movement in other way than just moving away from the melee knights. Connection with the theme of poison was also tenuous (through the spell #3).