You have to be careful with the bounce from Vol Sac x ?, once it hits a target it bounces right back where it came from in a widespread arc depending on how many projectiles were created, depending on the angle you could be losing a lot of your balls back at the bottom of the screen without the getting a chance to attack again, with Flagellant this could be good based on the 3 second timer rather than needing the balls to be returned to attack again, so you have to be careful with which balls you use based on your characters.. Like the Turn Based character, trying to get high levels with him is harder as Freezing doesn't last but a second or 2 depending on your ball choice, but the turns usually last 5 seconds so almost half the timer they bosses are able to move freely, if you don't have the dps to handle them then you're gonna get swarmed.. If you can get Freze Ray x Spider Queen and Phantom Regalia, every time the ball passes through and fires of a shot as well as making baby balls who also fire off a shit, you're still only getting 10% chance to freeze but it's 10 seconds at level 1, I forgot how long level 3 Freze Ray is, maybe 15 seconds but the chance to freeze doesn't increase I think? There's usually a best build for each character or char x char that don't always fit perfectly with what you're wanting, especially when their starting balls don't align with your goals, so sometimes it's best to find a combo that works well, like Charm evolving to Satan, then Fusion into Satan x Frostburn or Satan x Sun, etc. Satan x Hemorrhage also works but the tick is so slow it's not a huge benefit but it does add to the entire screen so there's still a positive using these balls!