We will be using
fractional multiclassing for mixing saves and BAB progression of monsters and classes. Overall, this will be a little more math but make your characters tend to be stronger. Let me know if you want help doing the math for your monster.
Young characters (mechanically young) count the same in terms of CR as other characters. NPC classes count the same as other classes.
Adding class levels: I have a system for adding class levels to monsters. If it turns out to be broken, we’ll tweak it. But it’s intended to keep monster PCs from getting too out of hand. It is not the same system as that listed in the pfsrd’s Monster Advancement section. IMO, that section exists for GM’s to make interesting monsters, where there’s less of an issue of GM’s making overpowered monsters that break the campaign. For PCs, there needs to be a more careful balance. Here’s the system:
1. Adding a class level grants you the additional powers, hp, bab, saves, etc of the class. So your first class level grants you an extra feat as does your third. Your fourth grants you +1 to one ability score, etc.
2. Adding class levels will not grant the big +4, +4, etc bonuses to ability scores. This is a major difference from the “Monster Advancement” section of the pfsrd.
3. You do get to pick a favored class and you get a favored class bonus whenever you take a level in that class. If you’re interested in a race-specific favored class bonus for your monster, we can discuss options.
So the only way to get class levels is by adding them in the way described above and they only grant the powers that PC levels in a class would grant (fcb, feats at odd levels, etc).
For the most part, your stats will be the same as those of the monsters you chose from the bestiary (HP and background skills being the main differences as explained below). Whatever skill ranks, racial bonuses, feats, etc that monster has it what you have. Those stats can then be modified as you take templates, class levels, or grow into a more powerful but very similar monster (e.g. a ghoul becoming a draugr) such that you still have continuity of the same character.
You will start off as CR 2 monsters. You may apply non-mythic templates as long as you keep a net CR of no more than 2 and as long as you have no more than a total of three zero or negative CR templates. No humanoid (or monstrous humanoid) creature types!
You may play any non-humanoid monster that could reasonably work for an evil wizard in her lair in the woods and then go adventuring. So poltergeist is out, for example, because it is bound to a specific site. But whatever you play must be capable of communicating with the other party members. So you have to be capable of speaking some language or telepathy. And the party will need to have some language in common.
To help with that, you get two background skills ranks for every CR you have. Max ranks in a skill will be based on your CR or HD, whichever is higher.
You will want to consider level-up possibilities when you choose your monster. Monsters may take class levels (with each level counting as one CR) but class levels may never be more than half your CR. You might want to play a monster that has a power progression already, such as most elementals, dragons, etc. You can take and re-spec as we level to make things work out. For example, your young blue dragon monk 2 (CR 11) can become a young (-1) adult blue dragon (CR 12). There will be a lot of options for how to do your progression. But your character shouldn't change so much as to disrupt the concept. E.g. your advanced dryad warpriest 4 shouldn't become a vampire. In addition, there should be a match between what your monster is RPing, learning, practicing, how its changing, etc that matches the mechanical change upon leveling up to a higher CR.
Banned stuff: Class templates (e.g. wizard creature), mythic templates, anything that comes up as game-breaking, blood money
Allowed templates: All paizo and some 3rd party upon request and GM review.
No starting equipment except for what the bestiary says you would have.
When you take your first class level, you may take traits.
The first hit die that you gain you get full hp. After that, you get the avg rounded up (d8->5, d10-> 6, etc) at each hit die. Monsters don't get favored class bonuses.
