Le Roux

Now for the actual tiers:

Maggot tier: Maggot deserves its own tier. Not only it has the highest damage output (by at least a factor 5), but it makes any AOE and status effect screen-wide. Best damage, largest equivalent-aoe, and moreover a lot of fun: wipe the screen with a cluster nuke, fill the screen with ice shards, insta-kill everything with a holy laser, the possibilities are endless...

Top tier (balls you should take any time you can):

Any multiball effect (brood mother, egg sag, cell, and their evolutions ). When combined with any good ball, the baby balls inherit from the other ball properties. All those balls are very good unevolved and awesome after an evolution, hence depending on the situation you can look for an evolution or not.

Blizzard: best crowd-control effet, already powerful before combining it with a multi-ball effect. Charm and succubus: they require a combination with a multi-ball or a screen-wide aoe before they are effective, but once it's done, ennemies are just flying away. I'm not sure Succubus is worth this, but healing faster than you can be wounded is so fun...

Glacier: for some reason the shards from glacier deal 10 times the damages of the shards from similar balls; good control, good AOE, awesome damage.

Hemorrhage: deals damages in percent of the enemies life. Alone, it is a very good boss killer; in combination with a multi-ball or a screenwide AOE, it is an OK crowd control.

OK tier (to combine with one of the above):

any beam; maybe the holy laser deserves the good tier, it seems to deal much more damages once mutl-balled. Note: test your multi-ball with a beam, it's easy to see how much it proc.

Screenwide aoe (flash, flicker, sun): combine with some good status effect.

Magma, swamp, and other aoe.

Assume everything else is in the trash tier; I don't have enough characters to indicate the "sometime useful tier" and the "fun tier".

All of this is... So wrong.

Satan of an OK ball. It does some ok crowd control. Its problem: it consumes one succubus, which can be used in several auto-win combo (combines it with any strong multi-ball effect, and see every ennemies flee away while you heal faster than you can take damages) and another charm effect, whitch is the best crowd control in the game (combine it with any strong multi-ball effect or a screen-wide aoe, and nobody attacks you ever again). Satan is fun, but it is the worst use you can do of a succubus or two charms. At least, it is useable, contrary to...

... Nosferatu is the worst ball in the game. Spider queen x Vampire lord is probably a win (although not the best use of a spider queen), Nosferatu isn't really any better. Nosferatu uses a spider queen, the second best multi-ball effect (there are so many auto-win use of a spider queen, it's not even fun to count them), and another brood mother, for a "meh" effect. But nosferatu is even worse than that: Nosferatu forces you to have a (non-fuzed) spider queen + a vampire lord + a mosquito king, ie a very weak build. Spider queen is excellent for its ability transform any decent ball into a screen-cleaning abomination, but an unfused spider queen isn't very good (and it's still better than a mosquito king). Inn other words: if you don't die while trying to create the nosferatu, it means the difficulty level is too low and any build would have won easily; a radical would have won. In other word, ether you die trying to create your Nosferatu and it proves it was a bad idea, ether you're able to create a Nosferatu and it proves it was useless and anything would have won. There is no sweet spot where Nosferatu is the best choice.