Balance Collapsing Void in line with Evard's

[Egon the Monkey]

So, yes it's one level higher, but it's also incredibly common on raids and it's even better than pre-nerf Evards. Great damage, spammed paralyse, and scales to the number of enemies well.
It would be fine if it kept  you in the Hole by spamming Slow, but Paralysis just makes it GG. Especially as it doesn't seem to be a one-round re-applying duration like say, Heart Clutch.

Evard's got nerfed because it was just too good. One black hole can just oneshot an entire frontline and mean it's too dangerous to run in and heal.

Could it be reduced to just Slow you, which is stull brutal with AOE damage and gives a rare Fort Slow?

[Abala]

You want me to balance a spell around NPCs using it on raids?

No.

[Egon the Monkey]

No, I'd like any DM willing to take the time on it to balance it. I would have just suggested 'take it off Voidcallers', except for the fact it punches way above its weight in all circumstances. I just picked raids as the example, because it's the worst case scenario due to the cramped spaces and Persistent AoE Bug. Not only is it incredibly powerful, you can't even see it's there. It kills PCs without any clue they're in danger.

I think it's just as overly strong in PvP, it's just we've not yet had a Bandit Astrologian go round disappointingly one-shotting entire parties with black holes to prove the point. I used to PvP with Original Flavour Evards back in V2. Even that didn't hold a candle to this WMD of a spell, because you can overwhelm Evards with more victims than tentacles. 

It's an exceptionally thematic spell for Astros and looks damn cool. It's just no-fun to be hit by as there's no good response to it other than 'hope a mate has Remove Paralyse and you make the next save'. There's nothing you can even do to prepare specifically for it as it's pure fortitude. Unlike Fossoris Fear Spam where you can crack out the Fear Saves Gear.

It's Simply the Best, Better Than All the Rest
I don't have to be PvP ganked with this thing to realise how it's a bit excessively good. If we compare this thing to the other options for L4-5 AoE on any class, there's no contest. It's a non-mind affecting total disable, with good no-save damage. And it locks down a Huge area for at least 9 rounds.  The only thing that even comes close is Cacophonic Burst. Except that is an instant effect, respects Insulations, and doesn't stop your mates running in to heal. The saves might degrade each round but that's more saves to pass than Hypnotic Pattern. More damage and a better debuff than Cloudkill. Way, way more dangeous than Sand Storm.

NPCs Fire More Offensive Spells
Besides, I'd wager 95% of all offensive spells fired are fired by NPCs, because they burn spellslots like there's no tomorrow. So yes, I think there's a strong case to review any spell that appears to wreck parties in a way they couldn't have countered. Because these spells aren't fun. Fear is fun as people get to react and save you with cheap potions. This is just 'sucks to be you' if you're in the middle.