After consideration and thought on the comments on the post I made last week, I've decided on how to modify the Sunlight spell. For more modifications to spells for my DF game, see the Revised GURPS Magic for DF page.
Sunlight
As DFRPG Spells, p. 48, but with the following additional sentence at the end of the first paragraph.
"This spell must be cast on the terminus of the light - it cannot be cast in midair, over a gaping chasm, etc. to reach the bottom."
I think that takes care of the main issues we've run across with range penalties and how to cast the spell.
How will you handle multiple terminuses, such as a ledge where the spell area continues over the edge and down to the bottom of a cliff?
ReplyDeleteThere are two choices - make it to the further point away, and thus an exception to the way Area spell ranges are calculated, or have the spell fail. The easier one - that works from below or above equally well - is the that the spell just fails.
DeleteOr...you could say to the player who is trying to game it in that situation (if that's what they're doing), "OK, so half of your Sunlight spell is at 0 yards distance, and the other half is 300 yards, so I'll be fair and only penalize you for half of the range penalty, so -150 to your roll. Good luck not critically failing!"
DeleteOn the other hand, if the person isn't being cheeky and it's just an unusual/weird situation, I think that either the spell fails or they specifically exclude those hexes from the area as per DFRPG Spells p. 13 to avoid spell failure: "You may choose to affect only a part of the area instead of the whole circle, but the cost is still the same – i.e., you may create an area of effect with 'holes' in it, but must still spend energy as if you had filled the entire radius."
That does sound like the easiest way to handle it. I can see a lot of attempts to provoke edge cases, though. "What if I throw a rock up into the shaft of light just as the wizard completes the spell, so that there's a level up in the air?" (Probably "make a critical Throwing roll to get the timing exactly right" at best, but more likely "yeah, no, a throwing-sized pebble doesn't count as a surface for this purpose".) "What if we get a Flying Carpet in between…" (I dunno, that one might work. Maybe a Quick Contest of IQ to place the Carpet properly?)
DeleteSee Vic's answer, I think. A flying carpet? Sure, you can center it on the carpet, just like you could on a boat. The range is to the carpet. Going to fly the carpet down? Go ahead, that's adventuring. Feel free to do that.
DeleteA rock? A rock isn't a terminus, it's too small, and wouldn't be a viable "area" for a Rain of Fire or Smoke or Darkness spell, so why this spell?
The edge cases, I think, will almost always be an easy "no" - less edge case than rules-lawyering.