I have a home brewed rule for Sorcerers please feel free to comment, provide feedback, thankyou.
House Rule Sorcerer Cost Current Suggestion 1 Doom Point. Replace a Cultist with a Sorcerer
Each player may have a maximum of 1 sorcerer
Special Rules. When you summon a sorcerer you can choose one of your faction or a neutral spell book. You can use that spell book as if it was one of your own however it does not count towards your 6 spell books to win the game.
A Sorcerer has 0 combat and can be captured like a cultist, however the soccer is sacrificed by the faction who captured him in the doom phase. Return the Sorcerer to the player in your doom phase when it is your turn to perform a ritual of annihilation, you may now perform the ritual of annihilation for 3 less power (tossing up between 3 less power, or half price rounded up, remember they player has played one power and gone to the effort of capturing the sorcerer so I am leaning towards half price.) If you do not choose to perform a ritual of annihilation then you gain no other benefit from sacrificing the Sorcerer.
Action (cost 0) Apotheosis, remove the sorcerer from play, roll 2 combat dice, for each pain rolled the faction who owned the sorcerer gains one power, if a kill is rolled the player can place the sorcerers spell on their faction card as if they had meet the requirements for gaining that spell, the player chooses which requirement they have met.
When a player summons a sorcerer they can choose one of the following special character sorcerers. They can only have one special character sorcerer for the game, and only they may have that sorcerer. They can however choose to have either a basic sorcerer or their special sorcerer if they summon future sorcerers. The cost and method of summoning a special sorcerer are the same as a normal sorcerer.
Unless stated otherwise a Special Sorcerer has a combat power of 0 and can be captured and sacrificed in the same manner as a normal Sorcerer.
Instead of Apotheosis a special Sorcerer has the Transcendence ability.
Transcendence (Action cost 0) Remove the Special Sorcerer and roll 3 combat dice, for each pain rolled the faction earns a power, for each kill rolled the faction earns a doom point.
In addition each of the special Sorcerers has the unique abilities described below.
As an example I have only included Joseph Curwen currently, suggestions for other sorcerers are welcome, I am intending to use Old Whateley and Keziah Mason, a full eight would be appreciated. I know there are many options, I want to save ancient Sorcerers and possible priests for a second version for use primarily in the Primeval Earth Map (though they would be free to use anywhere).
Essential Salts (Free Action Cost 0) When you Perform a spell or Summon a monster you may remove one or more cultists who are in the same region as Joseph Curwen, you may reduce the cost of the summoned monster or spell by one point per cultist sacrificed.
Essential Salts (Action Cost 1) you may summon a cultist to the same region as Joseph Curwen, that Cultist may then perform an action.
Explanation of why I did what I did.
Cost, I felt a doom point was a good way to represent the Faction investing personal power into the Sorcerer, something beyond a normal power. It might be a bit cheap, but a cultist already costs one point. I am now thinking it might be a bit to cheap, but I am not sure if I should go 2 doom (payed each time you summon) or a doom and power point. Two doom might be good trading doom victory for spell flexibility.
I thought the idea of gaining access to a extra spell book to use without it counting towards victory sounded nice, that is the primary point of the Sorcerer.
I also wanted to provide a model that the Faction had to protect and that the other factions would really like to get a hold of. In that respect I think the Ritual of Annihilation bonus was a good move, it also accelerates the game, some games people forget the ritual and I thought the Sorcerer would point at it.
I guess many factions will choose to sacrifice the sorcerer if it gets in trouble, so other players have to be very sneaky to grab him (using special abilities or having 6 spell books) for a player with 6 spell books the idea of making their ritual of annihilation cheaper would be very attractive.
The random rewards felt right, magic has always seemed pretty chaotic and dangerous so I did not want the same level of certainty with reward at sacrifice that the high priest offers. Also the abilities of the Sorcerer seem a lot more significant so I think the bonus should be lower. I also like a less certain but alternate road to completing spell books, for some factions other players can do a lot to interfere with that. And that is part of the the game, but a second path seems ok.
Alternatives include roll 1 combat dice getting 1 power for nothing, 1 doom for a pain, and the normal bonus of a spell book requirement for a kill.