The heroic bosses really need to be looked at. I have defeated them, but as always with the other adventures, I wouldnt say i beat them because of skill, but rather pure luck based on the correct passive treasures.
Linzi is one prime example of this. I have beaten her, but there were many times where I could do nothing with my starting deck and just watched her obliterate me.
The same thing applies to other heroic bosses. One other examples would be the shaman with the ability to cast overload spells 3 times. When you decide to give them nuke that casts 3 times and usable to target your hero… well… good luck and have fun interacting with the game as you watch him burn all his mana to target your face and you just explode.
And please get rid of the extra mana for the final bosses. It is very shallow design and there is nothing fun about it when all you can do is hope that boss draws bad in the first few turns.
Their hero power is already OP, and giving them mana advantage just means there will be many times players won’t be able to recover.