[Powers] Dark Sun defilers and preservers

[Justaguy]

Dear hivemind, I’m looking for a correction check on some powers or maybe some tips on how to handle things differently. And of course, if you like these powers, enjoy!
First, some background.

Our group is thinking about starting a new fantasy campaign. Designing an entire setting from scratch is too time-consuming, so I mostly start from a premade setting and make some adjustments. A couple of days ago I bumped into the Dark Sun setting (D&D). The setting allows different brands of magic (arcane, priestly, ‘druidic’…) and psionics. Nothing special here, really.

But one concept caught my attention and is really interesting: arcane magic is life-defiling (it’s also turning the planet into a wasteland). Most wizards are defilers: their magic harms the life surrounding them. But some wizards have found a way to wield their powers in a ‘clean’ way, these are the preservers.

‘Basic’ defilers take the energy from vegetal life surrounding them (also bugs, small insects, etc). Master defilers take this a step farther, they have learned to tap other living beings to power their spells, all the while still defiling the environment. On the other hand, the preservers power their clean magic by working more slowly, and at greater cost to themselves. Master preservers supposedly have ways to power their magic almost as well as the master defilers.

Now I’m not really interested in how the original D&D rules handle this, so I started from the concept, not the original rules. I tried to figure out a way how to model this in Gurps, using magic as powers (we don’t use the default magic system anymore).
This is what I came up with.

The Defiling Power Modifier is pretty straightforward:
Defiling is magical (-10%) + nuisance effect (-5%), when working magic, the caster seeps a foul black foglike substance that everyone instantly recognizes as defiling magic. This is worth -1 on reaction rolls, instantly marks you as a defiling spellcaster and may provoke violently hostile reactions from some people. (Question: is this worth more than -5%?). Total PM -15%.

Preserving is a bit harder and is treated later.

Now let’s go to the core abilities of defiling and preserving.

Defiling:
Lifebane (one ability, only while defiling Energy Reserve is regenerating, -80%) [-2] + defiling ER (arcane magic) [3] + very fast regeneration 1 (FP only, +0%; PM defiling, -15%; dedicated to defiling ER only, -50%; accessibility, requires vegetal life in a 3-yard radius, -20%) [20], total [21], or [18] without the ER, which can be bought separately.
Extra levels (maximum 1 level per talent in arcane magic) add a higher level fast regeneration, costing base 110 points for 2 FP/second, 115 points for 3 FP/second and 120 points for 4 FP/second. Cost for levels 1/2/3/4: [18/20/21/22] + cost of defiling ER. The defiling ER can be bought up at (arcane talent)x4 max. A defiler who wants to defile faster than this, will have to become a master defiler, leeching FP from the creatures around him in addition to defiling nature!

Questions:
- Is lifebane appropriate? I used the ‘one ability’ limitation from neutralize, appropriate?
- Should I allow the ‘special recharge’ limitation on the ER? It doesn’t seem fair since it regenerates anyway, but when there is no vegetal life around the caster, the regeneration doesn’t work. This is a limitation… Edit: the ER doesn't recover like regular FP, it only regenerates with the defiling regeneration ability.
- Regeneration dedicated to one ER only, not to regular FP or other ER. Is -50% appropriate or too generous?
Edit: questions answered, see post #8.

Master defilers:
Powerful defilers have the ability to power their spells by leeching energy out of the living beings nearby, all the while casting their spells and defiling vegetal life. I tried a link-approach first, but then I came up with compartmentalized mind, which is a lot cleaner and certainly cheaper than buying links on a whole bunch of abilities.
Compartmentalized mind 1 (one ability, defiling leech only, -80%; PM arcane, -10%) [10] + leech 1 (accelerated healing, +25%; decreased immunity 3, -30%; malediction 1, +100%; ranged, +40%; only heals FP, -20%; steals FP, -25%; heals defiling ER only, -40%) [38], total [48]. Extra levels add 1 level of leech at a time, allowing the defiler to steal 1 extra FP per turn. This costs [+6/level].
Skill: defiling, Will/H (+arcane talent).
There is no upper limit to the level of this ability. Master defilers can be very powerful indeed. Of course, there is no point in buying a leeching level higher than the FP a single average victim can provide (around 10) and the size of their defiling ER (4x arcane talent). This ability works at the same time as regular defiling, since regular defiling is a passive ability.

How does it work? Every turn, the compartmentalized mind dedicated to the leeching defiling ability, allows the caster to leech 1 FP per level from a victim nearby, while at the same time casting another spell or attacking (see B43). The leech takes -1/yard penalty to his skill and must win a quick contest (skill-/yard) vs his victim’s Will (+modifiers). Willing victims can waive this resistance roll (most defiling leeches have willing minions). Each point of margin of success lets the leech steal 1 FP per level. This can only heal FP from his dedicated arcane magic ER. The leech can also try to steal FP from his enemies, but don’t forget the -1/yard penalty and the quick contest. Increased immunity also provides the victims with a very powerful drawback for the leech. If he fails his leech, the victim becomes a) totally immune to his ability for 1 day or b) permanently gains +2 resistance against this defiler’s leech ability (rules, see Psionic Powers 21).

Question:
- I don’t think this breaks any rules, but I might have missed something. Feedback please?
Edit: found a mistake in the compartmentalized mind formula, see post #8.

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