How to make dark spellcasting tempting and dangerous

[Mystify]

Its a common trope. There is good magic which is pure, and dark magic, which is powerful and alluring, but very dangerous and corrupting.

I have never seen a system properly great a proper balance between the two. Darkl magic shouldn't be stronger, but it should appear to be stronger and a fast path to power.

So I thought of a method to so that. Dark magics stated effects are, in fact, stronger than light magic. However, dark magic is taboo, and there is not much information available. It is common knowledge that it is dangerous. Each spell has some unstated negative effects.

However, if the spell has extra effects, they have to be written somewhere. Even if the DMG equivalent has a section called "The negatives of spells", and you keep the players from reading it, the DM still reads it. Then next time you run a campaign and he is a player. Now the player knows what the downside is, and the mysterious temptation is gone.

Of course, he could play like he didn't know, but it would be better if he truly didn't know. It also helps to tempt the player, not just the character.

To get around this problem, I came up with the idea of random repercussions. The list of random repercussions should be hidden and not read, but even if you do read it then its not as big a deal, since you still don't know what will happen. When a spell is used in a campaign, the DM randomly selects the reprecussion of the spell, and that is how the spell works in this campaign.

For instance:
Raise dead
by performing dark rites, you bring a person back from death.

Possible reprecussions:
1. Caster gains a ton of corruption, but spell works
2. Zombies. Nuff said.
3. Requires a sacrificial life force; if none is provided the caster's is used
4. ironic twist of fate. The person is brought back, but not to the end the caste desired. If he brought back an old girlfreind, she will turn out to not love him, for example. This will proceed to tear his life apart.
5. Dead person's body is possessed by a malevolent spirit.
6. Person is brought back to life, but their body is still dead. They suffer the agony of a rotting body, and will not heal or die unless the body is destroyed.
7. Balance of fate. Somebody else close to the caster will die in an ironic manner
8. half-life. The dead person must feed on life force to sustain themselves.
9. ghost. The persons spirit returns as a ghost, trapped in the mortal realm.
10. Failure. The person is not brought back, and the caster loses something important in the attempt. An arm, a leg, a few years of life, etc.

These will be weighted, so corruption is the most common result. This means the spell works as advertised, but gaining corruption would have long term negatives, and would probably feature elements of addiction. This means you can't dismiss the spell as not working. It might work. It might go horribly. wrong. Its risky and dangerous, but you know that just due to it being dark magic, reading the options doesn't change that.
The actual reprecussions are not told to the player. Any corruption is tracked by the DM. Downsides are not stated, but the results of the downsides are told to the players. They can observe that the raisee is feeding on people's life force, but that it is an effect of the spell is never stated.
If corruption starts having effects on the character, they are told the effects, but not the source. They can only track their corruption by seeing the effects it has on them. This also helps lure people to dark magic. It works, nothing bad seems to have happened, so they keep doing it.

[Thomar_of_Uointer]

You could simply add a Corruption component to certain spells, or write new spells that are powerful for their level but have a Corruption component. Nasty stuff like ability score reduction, or minor penalties to checks, or the UA system (http://www.d20srd.org/srd/variant/campaigns/taint.htm).

An alternative would be to make power components (outlined in the Eberron Campaign Setting) that must always have a nasty background. The spells in the PHB are the "safe" amount of power a mage can use, but it's easy to use nasty material components to make them more dangerous at a risk to the caster. For example, the ear of a human who was no more than one year old could be used as a spell focus to allow no save against any audible illusions (ghost sound), but the caster must make a Fortitude save or become deaf for 24 hours. You could come up with more nasty things for higher-level effects, like a human heart as a material component for raise dead to create a zombie with +6 Strength and +6 Dexterity, but you must make a Will save each time you issue orders or it attacks you instead.

The neat thing about using power components is that it requires little effort, the whole thing is just an optional addition to the normal magic system. If PCs find out about these components they may choose to use or not use them. If you want to define certain spells as being evil, you just make the power component mandatory (with or without a bonus, just add the drawback you wanted).

[Mystify]

You could simply add a Corruption component to certain spells, or write new spells that are powerful for their level but have a Corruption component. Nasty stuff like ability score reduction, or minor penalties to checks, or the UA system (http://www.d20srd.org/srd/variant/campaigns/taint.htm).

An alternative would be to make power components (outlined in the Eberron Campaign Setting) that must always have a nasty background. The spells in the PHB are the "safe" amount of power a mage can use, but it's easy to use nasty material components to make them more dangerous at a risk to the caster. For example, the ear of a human who was no more than one year old could be used as a spell focus to allow no save against any audible illusions (ghost sound), but the caster must make a Fortitude save or become deaf for 24 hours. You could come up with more nasty things for higher-level effects, like a human heart as a material component for raise dead to create a zombie with +6 Strength and +6 Dexterity, but you must make a Will save each time you issue orders or it attacks you instead.

The neat thing about using power components is that it requires little effort, the whole thing is just an optional addition to the normal magic system. If PCs find out about these components they may choose to use or not use them. If you want to define certain spells as being evil, you just make the power component mandatory (with or without a bonus, just add the drawback you wanted).
I want a system with a more intrinsic divide. Adding on components to existing spells could be a branch of dark magic(corrupting spells into dark magic), but I am talking about a hypothetical system where this divide is present at the heart of the system.

[Yitzi]

The essence of the problem is how to make it so that dark magic is not stronger, but appears stronger even to a veteran of numerous games.

The only way I can see to make it work is that dark magic actually is mechanically stronger (higher CL, more powerful spells, or whatever), but provokes the ire of powerful good (and perhaps even neutral) -aligned beings. This would be going on "behind the screen" rather than in the mechanics, so unless the players think about what's going on (possibly with help from NPC messengers warning of the consequences), the dark path will look more powerful.

[Curious]

You could always invoke the whole 'magic has a price' shtick. Maybe dark magic takes a hefty toll on you, or maybe it avoids paying that toll. Cast from HP should be avoided. Maybe using dark magic could inflict some kind of (spellcasting stat) penalty, or daze you, or some such.

[JoshuaZ]

Heroes of Horror has a very similar suggested system for resurrection magic, with a list of random repercussions.

[lsfreak]

A potential option for making it appear better would be not the actual effects of the spell. Rather, make them able to be cast outside of certain normal restrictions. Take hellfire, identical to fireball in every way except one of the following:
- It is cast as a move action, though you cannot cast a standard-action spell this round
- It can be cast spontaneously by a wizard
- It can be prepared by a cleric despite being a wizard spell
- It counts against your 2nd level spells/day
Then combine this with drawbacks as in your first post. This means that spells are not mechanically more powerful in the way higher DC's or more targets would be, but are easier to cast. After all, many instances of the trope are not dark magic = more powerful, but dark magic = easier (and thus for a given amount of study, the casters themselves are more powerful).

[CharityB]

I like the limit break idea! You know how some spells have a cap on how many die they can use up? (fireball has a 10d6 (http://www.d20srd.org/srd/spells/fireball.htm) cap, for example) -- maybe you could break that cap through the power of evil!

[dspeyer]

Usually the effect of dark magic is that it is addictive and corrupts the soul of its user. Drawbacks that effect the PC's mind are hard unless the player is very co-operative.

You could have it effect perception, though. If you've used a lot of dark magic recently, you see a monster charging you when in reality it's a police officer. As you're standing over the bloody corpse you never meant to kill with no usable excuse, you become aware of another dark spell that will make all the witnesses forget...

[Thomar_of_Uointer]

There's a nice list of possible side effects for black magic here: http://www.d20srd.org/srd/variant/campaigns/taint.htm#effectsOfTaint

[drew2u]

Perhaps Dark Magic is easier to perform with a caveat that includes some sort of addictive nature and something akin to Taint that other people have been suggesting?