Swarm stuff, advancement -, and cr.

[Falontani]

Going to preface this. I know, I know. I'm the dm. I can do whatever I please. But I would like to keep this within the rules as I have players with vast amounts of system mastery, that get butthurt when I break the rules, but absolutely love it when I do something awesome and unique while following them.

As always, if your one of my players keep out.


I want to use a swarm. This swarm has intelligence, but does not have the hivemind ability. This swarm has Advancement: -. I can advance it with templates, and it is a living outsider. But. I want to give it casting. In a villainous competition a ways back I used a cranium rat swarm, but it seems to advance swarms usually you need the hive mind ability. Ideas? Any ideas used that aren't templates, please show me how to do it within the RAW with CR adjustments.

[Mike Miller]

Which swarm is it? So I have a point of reference...

[Falontani]

Broodswarm from Fiendish Codex 1

[Segev]

Nothing prevents you from simply giving it class levels. Though it is weird for it not to have a hive mind. That suggests that the creatures are each individuals, just acting in a swarm. So each one advances as a caster on its own?

Maybe have one or more exceptional members of the swarm that have class levels, and technically are members of it for protection. Can’t be targeted individually without dispersing the swarm because they can’t be distinguished. But getting to act on their own initiative, only moving either the swarm.

[Crake]

Advancement follows the same rules as alignment, in that they are just a guideline, not a hard and fast rule. "Always X" alignment means 99% are that alignment, while "Advancement X" means 99% of the creatures fit within that advancement category.


Advancement
This book usually describes only the most commonly encountered version of a creature (though some entries for advanced monsters can be found). The advancement line shows how tough a creature can get, in terms of extra Hit Dice. (This is not an absolute limit, but exceptions are extremely rare.) Often, intelligent creatures advance by gaining a level in a character class instead of just gaining a new Hit Die.

That said, for broodswarms particularly, I would imagine the swarm of them is kinda like a mob of bacche, or the squad rules in heros of battle, they are each individually intelligent, and kinda work together as a group to act as something of a single unit, but they are still each unique individuals, so it wouldn't make sense to give the swarm itself class levels, unless you had them learn some kind of gestalt casting I guess?