I like the idea of spirit/godling/demon patrons but I don’t like that they are restricted to a certain class. Fighters should be able to channel the power of the damned just as much as a wizard. I finally got the light bulb last night while working on the idea for Alternity- artifacts/relics. Every power and drawback for artifacts in Alternity has three levels of power, thus allowing for reactions from the patron over the actions of the character. It shouldn’t be that difficult to work that into other games.

Using the 2e Book of Artifacts (which is a pdf on OBS), one could use the charts in the book (directly or as inspiration) to design many, many blessings of dark gods that include the negative side effects of conducting such power through the character’s body. Artifacts without an actual artifact in hand as it were. They could be modified by the whims of the patron, removed or turned entirely negative if the character and patron have a falling out and best of all, provide a power up to formerly weak foes the player characters passed by. That brownie the players screwed over in their second adventure may come back evil and with the ability to transform into a troll or wyvern, a gift of his demonic patron. Of course he also has to deal with the negative side effects- warped appearance, kills plants with his touch and hatred from his family and other fey kin.

A couple other sources of inspiration are Distant Horizon’s Eclipse: The Codex Persona, which contains the best how to build pact maker advice in the witchcraft section and Sine Nomine’s Black Streams: The Pacts of the Wise, which provides useful patrons and rules for OSR warlocks.

 For an example, I decided on Voorqual, the central creature to this story by Clark Ashton Smith:  http://www.eldritchdark.com/writings/short-stories/41/the-demon-of-the-flower

Voorqual is the master of demonic plants and to make things simple, I am using existing monstrous plants and calling them demon possessed creatures. Those who want to add templates or other ways of providing demonic power to the vegetable critters, go for it.

It provides several different powers (drawn from The Book of Artifacts): Purify Food & Drink (at will), Repel Insects (at will), Monster Summoning VI (hangman tree, shambling mound or treant, 1/day), Create Water (10,000 gallons per day, quantity per use up to the character), Transmute Rock to Mud (as 20^th level caster, 3/day) and couple powers not in the book, understand all plant traits and uses (5 rounds per plant) and infest foes with demonic seedlings (treat as mummy rot, death frees 2d4 yellow musk creepers which are mobile for a month). How many powers and which ones the character gets are determined when the pact is made and how much of a price is accepted.

The potential prices (drawn from Codex) are Taboo (the character can not willing harm a demonic plant), Ritual (the character must visit Voorqual once per year and provide 50 hit dice worth of animal and/or human sacrifices), Corruption (the required price; the character becomes more and more plant like and eventually is possessed by a demon) and Gateway (when a pact spell is cast there is a 20% chance that a plant within 100’ is possessed by a demon, this creature is neutral to the caster and hostile to most other beings, including the caster’s non-vegetable allies). Breaking the taboo or skipping the ritual is a good way for the corruption to accelerate or a variety of demonic plants to start hunting the character.

So you see, the character is damned but gets some nifty toys to play with before they are sent to the vegetable abyss.