treat defilers as warlocks (infernal pact)?
Just add the effect of defiling (plant life turned ot ash).
This would make sens ein many ways and be easy to implement:
1) Warlocks, as in a normal D&D game, should not be in Dark Sun games except...
There's only two kinds of arcane caster in Dark Sun: preserver (wizards) and defiler.
Defilers are more powerful than wizards, had this arguement several times but as I keep pointing out, defilers are more powerful because they wiped the preservers out.
END OF STORY! ;)
2) Now then, if you make Defilers as "warlocks with infernal pact", you can justify the previous items!
-Warlocks are more lethal, single target, than wizards, they are strikers, where as wizards are controllers. Go check single target damage and effects between each of them.
-Warlocks are more damaging on 1 target.
-Also, Infernal pact warlocks get lots of nifty but nasty powers that make them tougher (like draining health).
-Destroying life to get their power is perfect thematically. Also lets folks who preffer alternate histores of Athas come up with their own explanations for defilers (diabolic interference, Asmodeous plan to destroy life or whatever)
-Using warlock saves having to make new spell caster class or rules. etc.
Just add the defiling effect to a Warlock (infernal pact) as "Defilers" and you have everything but psionics in 4th ed Dark Sun, now
I believe that it's very, very important, thematically, not to treat defiling as a particular class: Rather, it's an aspect of Arcane magic. This is one of those things that goes to the core of the setting fluff.
Never mind the various occasions where wizards resort to defiling in a panic effort. Something which I think may be easier to represent in 4th edition than it was in 3rd edition -- the ability to boost your spell traits through the use of implements is considered as a part of the 4e system, and "signifigant" defiling bonuses thus aren't as likely to break the balance of the game as they were in 3e.
As a counter point, I actually think that the framework of the Warlock works very well for our three "non-defiling" wizards -- the exception to this general rule -- Necromancers, Shadowmancers and Cerulians.
I've touched on this a little bit at the arena: http://arena.athas.org/forums/ds-4/
Defiling renders infertile and destroys plants in the effected area. It also causes pain to creatures in the area.
The pain is represented by an attack: Int vs Fort, Hit: creature loses one healing surge. The defiler is not affected but his allies are.
The area is a number of squares based on the type of power:
at will: 1
encounter: 9
daily: 25
closest squares are affected first, so if the defiler never moves the defiled area is a burst that grows a little with every spell cast. Contiguous previously defiled squares are considered part of the defiled area (they cause pain) if they are closer to the defiler than the farthest square that becomes defiled.
Preservers have the following power:
Long Draw
minor action, at will:
you may defile to gain a +2 attack and damage on the next spell that you cast until the end of your next turn. Until you save you must use this power before casting a spell, and you do not get the +2 bonus to attack or damage. Make saves only when attempting to cast a spell without defiling. Permanently becoming a Defiler grants an automatic success on the save and so you no longer need to use a minor action to cast spells. Defilers can become preservers if a Druid of greater level casts Atonement. Druids generally kill defilers on sight.