I'm still a PrismSpec4ever guy, i like the dmg boost.
Crono Luminaire, Lucca Flare and Magus Darkmatter, i mean, what do u want more? after 4 attacks of each(19mp remaining), use a MegaElixier.
Crono confuse left bit, gets ether, lavos core shuts def down, cast everything till the end, win.
I think i remember beating lavos this way at his first shut def down...
Like the 1 round for Queen zeal, luminaire+squash+dino=instant win
PrismSpecs for everyone