Epic Hivemind Design

[AvatarVecna]

Say you're DMing for a low-epic game where, as part of a more-or-less universal "Gentleman's Agreement", infinite/NI loops are banned, and Epic Spellcasting is allowed, but abuse of it is discouraged. This leads to interesting quests where people track down esoteric means of gaining massive amounts of power to deal with other people of their stature, and one such Evil chucklenut has gone and Dark Speech'd a Ruin Swarm into becoming a Hivemind for unclear reasons. Whatever he expected to get out of it, it didn't work out for him and now the Hivemind has taken charge of his organization (cult? wizard school? political party? ehhhhh).

So now you've got this bad boy (https://www.d20srd.org/srd/epic/monsters/ruinSwarm.htm) as the new villain - maybe "villain of the week", maybe "new BBEG for the campaign", you haven't decided yet, but deciding that will be part of the design step - except in addition to their existing stats, they have Int 27, Cha 49, cast as a Sorcerer 32, just gained 400 skill points, and just gained 400 feats. These feats can, at least theoretically, all be epic feats, since they were gained at HD 50.

How do you assign skills/spells known/feats to make your interesting villain?

[unseenmage]

If you're actually using the Hivemind from BoVD then there are a few rules issues you should beware of.

As written, after the hivemind forms theres no reason the constituent creatures have to stay together. They can scatter far and wide while their combined mind remains intact.

One constituent creature could be part of multiple hiveminds. Which allows for Instantaneous information sharing and backup of information.

Both of the above points are largely moot as you seem to be using a swarm. Unless you're using multiple swarms.

As written if a single hivemind-ed creature takes enough damage to kill the whole hivemind then the whole hivemind dies, regardless of distance from other hivemind members.

There is also some question about targeting the hivemind as a single mind but multiple creatures; Which takes precedence?
Allowing one save-or-die effect sounds like a good idea until you realize that it also let's the spellcasting mass target all of itself with buffs too.

[AvatarVecna]

If you're actually using the Hivemind from BoVD then there are a few rules issues you should beware of.

As written, after the hivemind forms theres no reason the constituent creatures have to stay together. They can scatter far and wide while their combined mind remains intact.

One constituent creature could be part of multiple hiveminds. Which allows for Instantaneous information sharing and backup of information.

Both of the above points are largely moot as you seem to be using a swarm. Unless you're using multiple swarms.

As written if a single hivemind-ed creature takes enough damage to kill the whole hivemind then the whole hivemind dies, regardless of distance from other hivemind members.

There is also some question about targeting the hivemind as a single mind but multiple creatures; Which takes precedence?
Allowing one save-or-die effect sounds like a good idea until you realize that it also let's the spellcasting mass target all of itself with buffs too.

I'm thoroughly aware of a lot of the weirdnesses involved with hiveminds, including (as an example) that there's not really any rules for a hivemind ceasing to be, even if there are some common-sense applications that can be applied. I'm aware that a hivemind of individuals animals/vermin could be scattered far and wide while remaining in communication - in fact, it was one of my scrapped ideas for the recent villain contest, ie "is hivemind broken even if you limit yourself to a hivemind that can't cast" (the answer is yes, btw: a 70+ HD Colossal creature with hundreds of feats and skill points is a nightmare of a noncaster, so much so that being too strong to reasonably take on without cheaty caster stuff is what made me scrap it).

I'm not looking for general advice on how hiveminds work, I'm more looking for how people might outfit one based on what kind of group they expect it to face down, and how important it's going to be to the main plot. Certainly a version with 400 iteration of Epic Toughness is going to be a very different fight from a version with (for example) 400 iterations of Great Charisma. Looking for the kind of weird shenanigans people might consider getting up to for an epic villain who isn't just going "lol epic spellcasting".

[unseenmage]

I'm thoroughly aware of a lot of the weirdnesses involved with hiveminds, including (as an example) that there's not really any rules for a hivemind ceasing to be, even if there are some common-sense applications that can be applied. I'm aware that a hivemind of individuals animals/vermin could be scattered far and wide while remaining in communication - in fact, it was one of my scrapped ideas for the recent villain contest, ie "is hivemind broken even if you limit yourself to a hivemind that can't cast" (the answer is yes, btw: a 70+ HD Colossal creature with hundreds of feats and skill points is a nightmare of a noncaster, so much so that being too strong to reasonably take on without cheaty caster stuff is what made me scrap it).

I'm not looking for general advice on how hiveminds work, I'm more looking for how people might outfit one based on what kind of group they expect it to face down, and how important it's going to be to the main plot. Certainly a version with 400 iteration of Epic Toughness is going to be a very different fight from a version with (for example) 400 iterations of Great Charisma. Looking for the kind of weird shenanigans people might consider getting up to for an epic villain who isn't just going "lol epic spellcasting".
In my mess of an extended sig there's a thread about all the feats any creature can take costarring a whole slew of really good feats that have minimal prerequisites.
Might be a decent place to start.

Do you want a grey goo scenario or no? Because a hivemind interested in making more of itself is a different build than one meant to solo the universe.

[AvatarVecna]

I don't have anything in particular in mind for how it ties i to overall plot - that's more part of the prompt. At least part of it's also "advice on here is normally about maximizing power but im more looki g for making a villain worthy of being called epic that isnt just a giant headache to fight". Certainly replication wouldn't be difficult - it can probably qualify for Dark Speech easy, and can Gate in more Ruin Swarms without needing shenanigans. Of that's the kinda epic plot this thing's kicking off, what's the longterm goal and how do the feats/spells/skills support that?