That said given Maxos is an incredibly powerful wizard maybe he could get a unique general unit ingame in the campagin that basically is like an extremely powerful Warlock.
Can cloak himself, can polymorph multiple units at once after cool down (like maybe 5 cooldown probably same or greater than Warlock), has a shield ability and healing plus teleportation. Main weaknesse would be slow movement speed (he has no jetpack :P) and his protection could be scripted leaving him with relatively low health?