So i'm building this encounter for my PC's a bunch of LVL 4 characters. They are wandering around the forest and have come under assault by a brood of human sized spiders. Realizing what they need is in the den of the Clutch Mother our brave heroes are trekking into her underground cavern to root her out and cleanse the land of her presence.
What the PC's don't know however is that the Clutch Mother; an awakened giant black widow spider (from bestiary 2) is awaiting for them and has levels in necromancer after capturing, and consuming one that was in the forests doing usual necromancer things. She then learned from his spell-book and so forth. So here's the problem, there are no rules on awakening vermin (Yes the vermin heart feat would work on it) but the actual rules are messy enough as it is. Now this is my best attempt at it, and I would really appreciate others opinions on whether the math is correct or if the CR is appropriate.
CR breakdown: Base 3, Necromancer 5 (3 non key, 2 key) = CR 6
I don't have an immediate answer as I haven't had a chance to look through it, but what did you use to build the stat block?
You mean the actual block or the base creature?
The block template is something I have designed myself, and the base creature is Giant Black Widow Spider
note that the players would probably reach 5th before challenging the Clutch Mother
I don't know, it's basically an unoptimised 5th level wizard with extra hp. And an immunity to mind-affecting which she should probably lose being neither vermin type nor mindless now. CR 5 seems more appropriate. This assumes that undead created in advance using the wand are going to have their own CR.