Can Sleek create an undead the size of a small ball or something? Give it the ability to absorb (Sleek and his mages can pump a bit mana into it in their free time), store, and transfer mana to others. Like a battery/mana bank sort of creature. That would help with the mana problems. Since it's a container of pure mana, maybe Sleek can change it to his acid spell or something and toss it out as a kind of grenade in bad situations. The power would be determined by his chosen spell's level. And the range would be based off the amount of mana stored inside? It would give Sleek a big AOE attack and a sort of trump card, maybe...
Hm why doesnt he make a "spell" that actually enchances his system. Like scan or a info screen so he can see the mana in his skeles or a design spell so he can customize his skeles? Would say put this in later but just a way to get him a little easier into the summoning skeles
SageDrunkKitty