GURPS Dark Sun Conversion

[Pragmatic]

@ tetrahedron:

I think the problem most people will have with your system is, it has the same problem that all versions of D&D Dark Sun have had (well, 2E, 2E revised, and both Dragon and Athas.org 3.0E/3.5E versions... not sure of 4E version).

It puts a divide between defilers and preservers, when there should be a spectrum. Yes, defilers will all too often just be people who were never taught any better--that's the default after the Cleansing Wars (after the purge of the preservers). But there will also be preservers who will be tempted into defiling "just in emergencies."

All of which leads me into saying (after reviewing Threshold Magic in Thaumataology and seeing that you've set up the Threshold Magery up properly... :-P) that you should might want to allow multiple gradations (and multiple paths...) between 100% Preserver and 100% Defiler.

So, for instance, you might want a THM ("Threshold Magery") that costs 9 per level (Reduced Threshold 1 OR Slower Magical Recover 1, for instance), as a preserver gets used to the idea of sapping a little extra from the environment.

Also, maybe start awarding negative points towards disadvantages for particularly high "tallies." So, for instance (totally off the top of my head), every calamity check which exceeds the threshold requires a check against... I dunno, Thaumatology?... at +1 penalty (??) per 5 points above the threshold. Failure means 1 point towards a disadvantage from a list (to be determined). For full-on preservers, that can be points towards reducing the THM. As they get to be full-on defilers, that can be points towards conversion to a T'liz (see Dark Sun MC 2; the athas.org site had rules on becoming a t'liz, IIRC)--or simply picking up the Defiler Aura or what-not.

Still, like the work. :-)

Edit: Also, don't see any mention of how to roll above 23 (18 on 3d, +5 for "boulder fields, sandy wastes, salt flats), on your list there. I think you forgot to include your "repeated casting in one spot" or "+1 per 5 pts above threshold limit" rules...?

Edit 2: I'd also consider taking the reduction in THM costs (as the full-preserver slips towards full-defiler towards full-t'liz...) and letting the player spend them towards some of the minor variations within Thaumatology. For instance, Thaumatology p. 39-40. And if the nascent-defiler wants to work their way back to preserver, they lose these perks to pay for the increased cost of THM.

Oooh, and that could be a way of showing how powerful a defiler is, by having them purchase the difference in Defiler cost-reduced THM from Pure-Preserver full-cost THM. So, for instance, a Preserver Threshold Magery 2 costs 25 points. Whereas let's say a Defiler has a 20% reduction (whatever combination of limitations...), reducing it to 20 points. The five points saved have to be spent on perks for spells (e.g., "Fireball/Increased Range" technique at 5 points). Not sure what to do with the extra mana costs (e.g., "Fireball/Increased Range" at 5pts means that 2x range is +2 mana and +0 effective skill; 5x range is +4 mana and +0 effective skill; 10x range is +6 mana and -1 effective skill; and 20x range is +8 mana and -3 effective skill)...