what mc does to fireblast:
multiplies mana cost by 1.16
multiplies cd by 0.83333
memhack should be able to do this, right? change the numbers to make it a little more balanced, but this should be better than the weird mechanic where it drains extra mana when it procs.
what witchcraft did to carrion swarm:
12.5% per level cooldown reduction
9.4% mana cost reduction for first level, half of that on subsequent
though neither of these went on the ult which gained 3/4/5/6 ghosts instead. it could give you this mini exo on whichever ulti you use.
also 5% ms per level
the new witchcraft is fun enough to keep but we also have the technology for the old one now