The Living Scourge.

I would like to see what happens if at least one of the three Scourges is not killed at the start.
Seeing how they are typically knocked out at the beginning seems a little too convenient for the hardest boss in the game. This is in an environment where previous turns of the coil have had rather important responsibilities for a second tank. (Pass-the-parcel on ADS and separation-management on Cadeceus.)
It is also not unheard-of for lesser mobs to interact with a boss. Examples are Cadeceus' slugs, Suparna & Chirada, and the Tonberry King's rancorous army. Twintania's Scourges may follow this trend. It may be that the Twisters will target the Scourge if one is still alive (or even Conflagration for that matter). Or perhaps one less Twister spawns for each Scourge alive.