Thanks for the pointer. I've corrected my post above to include the proper code, and located SkillVsItemCost.2da, and it seems pretty straightforward.DaloLorn wrote: ↑Tue Mar 07, 2023 4:59 am All indications are currently that the UMD cost somehow scales based off of "skillvs"... something, something. I'm on the wrong machine to check what the full 2DA name is right now. It seems to track the item's cost and apply UMD thresholds based on that. (This cost, in turn, has very little to do with the scroll's CL at this time. IIRC, the scroll currently has a base cost of just above 1000gp? It's been a while since I bought any.)
In theory, we could zero out all the columns and add our own UMD enforcement in the on_equip and on_castspell hooks. However, no coherent proposal has yet been made for such a change, and it is likely that it would bring us closer in line with PnP rules. (Which probably means no more taking 20 on wands or other non-scroll uses of UMD, though we'd probably also strip out most class/alignment restrictions from anything except wands and scrolls.)
For an item with a class restriction worth 800-999 GP, the UMD modifier required to attempt use is 25. For a price of 1000-1199, the DC is 27. For 1200 GP and higher, it looks to be DC 29. A cursory glance at Sorcerous Sundries suggests that the price for a CL18 teleport scroll is over 1200 (and it probably should be: 5 * 18 * 25 = 2250 gp. With a +18 appraise, I am seeing 1230 GP for the scroll at Sundries).
This would explain why Snarfy is able to use a scroll when his character has a +29 UMD, while Steve is suffering with a +25.
Changing the scroll to CL 9 (as per minimum for scrolls of 5th level) would reason a price of 1125 GP (5*9*25), which would drop the DC from 29 down to 27, unfortunately still outside Steve's range, but at least we now know why.
Explanation of the 2da (For Dalo, I suspect)