Initially, he gets to keep the spell for 3 minutes with further level ups increasing it by 1 minute. I can see that being easily scaled down and up if we apply the RP's leveling system. In fact, I suppose we could apply that to his other spells which includes a bouncing bolt and a telekinesis lift.

As for upgrades, Dota does have a wide variety of equipment that he could obtain upon leveling up. How would we go about deciding what I would receive per level though? [@Holy Soldier]