Version 3.1.105 released 

• change: Stack splits distrubite 1 creature to the new stack instead of half of the original size
• fix: After level up hero max mana calculation does not take into account knowledge bonus from book of power.
• fix: Master of Fire perk substracted half defense from the moment of impact instead of half of the current creature defense
• fix: Encourage ability was affected by resistance
• fix: Elite Casters perk reduced mana for abilities

Main post was updated as well.

This fixes should make the base game more stable, not the opposite so I will appreciate if you test the bugs and provide feedback even if no issues occur. Just mention which feature was tested.