Idea for a new Hero - Warlock/Mage

I know we have a Barb King and Archer Queen Hero - but I think if we got a new Hero it would complete the Hero version of the Troops - for this I am thinking a Hero Wizard - instead it would be a Mage/Warlock and he would have a staff also. Furthermore, with each level up the Warlock would increase normally in the stats - but like the Witch the Warlock can do different spells/attacks. The Warlock is also a Dark troop like the Barb King and Archer Queen.

Finally, at the final level up the Warlock could have a robe and fireball hovering at the tip of the staff?

okayyy but how much would he cost?