Tempting Magic Subsystem

January 2011's Reader Article brings you an expansion on another cool thing Dark Sun introduced: defiling magic.  When an arcane spellcaster used a daily power and disliked a roll, he could reroll it once.  The cost?  The character's allies would take damage from the spellcaster drawing from their life force.  It brings up the possibility of great roleplaying moments and even greater moment between players, when an arcane player decides to use arcane defiling and cause an ally to drop to 0 hit poins.  A player could go into the game thinking, "I won't need to do that."  But the temptation's there.  Think about it.  It's not just roleplaying the temptation of the character, it's actually tempting to the player!

This nasty power is perfect for the DM to suggest in any D&D adventure, even outside Dark Sun, as long as you can agree that magic draws from life force in the same way.  However, it's unfair to the players who aren't playing arcane classes (or maybe it's a relief to them that they don't have to deal with the temptation, so it's unfair to the arcane players!).  Here are some ideas for adapting the power to be used by other classes.

DIVINE MAGIC

The special link that a divine character has with the gods is not exclusive to the gods he or she worships.  Other gods can use that link to communicate with the character, though the character can decide who to listen to.  Devils exploit this to offer deals to divine characters, deals that would grant them more power if they betray their god and their allies.  This deal doesn't require negotiations; it is always open, waiting for the divine character to make a hasty decision that starts him or her on the way to corruption.

If you have at least one divine daily attack power, you gain the divine dealing power.

Divine Dealing - Divine Feature
You make a split-second deal with shady divine characters, and sacrifice the energy of your allies in order to destroy your foes.
At-Will * Divine, Radiant
Free Action - Personal
Trigger: You make an attack roll or a damage roll as part of a divine daily attack power.
Effect: You can reroll the triggering roll but must use the second result.  In addition, each ally (willing or unwilling) within 20 squares of you takes radiant damage equal to half his or her healing surge value.  This damage ignores immunities and cannot be reduced in any way.
Special: You can use this effect once for any divine daily attack power you use, affecting any single attack roll or the damage roll for that power.

PRIMAL MAGIC

There are literally infinite primal spirits.  The spirits a primal character channels are only a fraction of those who want the help of mortals to further their goals.  Those goals differ from spirit to spirit.  Some spirits desire nothing but the destruction of the world.  They believe it has become corrupt with mortality, infected by the gods and primordials who kept bickering over it.  They are gleeful when anything is destroyed, so when a primal character opens him or herself up to letting these spirits out, they do so without allowing for a second thought.

If you have at least one primal daily attack power, you gain the primal slaughtering power.

Primal Slaughtering - Primal Feature
The most destructive spirits flow out from you, making your attack much more dangerous.  However, these spirits do not distinguish between your friend and foe; all should be destroyed.
At-Will * Force, Primal
Free Action - Personal
Trigger: You make an attack roll or a damage roll as part of a primal daily attack power.
Effect: You can reroll the triggering roll but must use the second result.  In addition, each ally (willing or unwilling) within 20 squares of you takes force damage equal to half his or her healing surge value.  This damage ignores immunities and cannot be reduced in any way.
Special: You can use this effect once for any primal daily attack power you use, affecting any single attack roll or the damage roll for that power.

PSIONIC MAGIC

The mind holds terrible secrets.  Practitioners of psionic magic have learned to manipulate the flow of psychic energy that every living creature emits.  This can be used without damaging those creatures, but if pushed further, using psionic powers can send dangerous ripples through the psychic flow that can cause temporary or sometimes permanent harm.  Interacting with someone creates a psychic link between you and the other person; allying with someone makes this link stronger.  It's an innate ability that every creature possesses in order to cooperate to better effect.  Psionic characters, when they strain their magic, also strain these bonds they share with their allies.

If you have at least one psionic daily attack power, you gain the psionic straining power.

Psionic Straining - Psionic Feature
Your allies feel pain as you draw their psychic energy into your mind in order to augment your psionic attack.
At-Will * Psionic, Psychic
Free Action - Personal
Trigger: You make an attack roll or a damage roll as part of a psionic daily attack power.
Effect: You can reroll the triggering roll but must use the second result.  In addition, each ally (willing or unwilling) within 20 squares of you takes psychic damage equal to half his or her healing surge value.  This damage ignores immunities and cannot be reduced in any way.
Special: You can use this effect once for any psionic daily attack power you use, affecting any single attack roll or the damage roll for that power.

SHADOW MAGIC

Probably the most common hero to fall to corruption is a hero who uses shadow magic.  They have already severed their soul, so the value of any creature's soul is lessened in their mind.  A shadow character does not need any outside powers to tempt them; they are constantly tempted to reach out and steal parts of the souls of others in order to enhance their abilities.  Doing so can be dangerous, but since the shadow character survived the loss of part of his or her soul, why can't others?

If you have at least one shadow daily attack power, you gain the shadow splicing power.

Shadow Splicing - Shadow Feature
Your magic did not have the effect you wanted, so you exploit the link between souls that joining forces creates and you snip off pieces of your allies souls to add to your magic.
At-Will * Necrotic, Shadow
Free Action - Personal
Trigger: You make an attack roll or a damage roll as part of a shadow daily attack power.
Effect: You can reroll the triggering roll but must use the second result.  In addition, each ally (willing or unwilling) within 20 squares of you takes necrotic damage equal to half his or her healing surge value.  This damage ignores immunities and cannot be reduced in any way.
Special: You can use this effect once for any shadow daily attack power you use, affecting any single attack roll or the damage roll for that power.

FEATS

Oddly enough, a character can take feats to enhance his or her ability to use arcane defiling.  Why would anyone take feats to make a power you don't want to use often better?  Because it makes it more tempting to use it more often.  It's a potentially vicious trick that can cause a virtuous character to end up a level 30 tyrant.  You should of course be able to use some of those feats with these new powers.  The following feats can be adapted to be usable along with the new powers.  Note that the text of these feats is not what it actually should say, but just a summary of how the feat works.  Also, I've come up with new feats that are for specific tempting powers.

ADAPTABLE FEATS

DEFILING ACTION (Dark Sun Campaign Setting, page 105)
- Prerequisite: One of the tempting powers
- Benefit: When you spend an action point to use an at-will or encounter attack, you can use your tempting power of the same power source with that attack.

DEFILING ADEPT (Dark Sun Campaign Setting, page 113)
- Prerequisite: 11th level, one of the tempting powers
- Benefit: Daily attacks that were used with a tempting power can score a critical hit on a 19-20 (18-20 at 21st level).

VICTIM'S DEFILEMENT (Dark Sun Campaign Setting, page 115)
- Prerequisite: 11th level, one of the tempting powers
- Benefit: Daily attacks that were used with a tempting power deal 4 extra damage (6 at 21st level).

DEFILER'S REJUVENATION (Dark Sun Campaign Setting, page 115)
- Prerequisite: 21st level, one of the tempting powers, 1 or more power points
- Benefit: When you deal damage to an ally with a tempting power, you regain 2 power points.

NEW FEATS

INFERNAL BARGAIN
- Prerequisite: Divine dealing power
- Benefit: When you use a divine daily attack power with your divine dealing, you gain 5 temporary hit points.  The temporary hit points increase to 10 at 11th level and 15 at 21st level.

PSYCHIC HAZE
- Prerequisite: Psionic straining power
- Benefit: When you use a psionic daily attack power with your psionic straining, each enemy you hit with the attack takes a -2 penalty to attack rolls (save ends).

REVEAL WEAKNESS
- Prerequisite: Shadow splicing power
- Benefit: When you use a shadow daily attack power with your shadow splicing, each enemy you hit with the attack takes a -5 penalty to a defense of your choice (save ends).  You can choose different defenses for each target.

SPIRIT WOUND
- Prerequisite: Primal slaughtering power
- Benefit: When you use a primal daily attack power with your primal slaughtering, each enemy you hit with the attack takes ongoing 2 damage (save ends).  The ongoing damage increases to 5 at 11th level and 7 at 21st level.