The Sigil said:
It was, in my view, the weakest of the spells included (in terms of effect versus spell level). I wanted to err on the side of weakness, however.
That's a good instinct.
On further review, I think you're right - the 15 dice may be a good cap to use. My concern was not so much with the damage dealt (even at 15d4 per round, that's only an average of about 37 points of damage per round for a 5th-level spell) but the "healing" aspect of it (allowing the caster to gain, on average, 37 points per round) as well as the "no save" aspect (common for ray spells).
Well, let's just see what
Heroes of High Favor: Elves has to say on the subject. (I didn't do all that research for nothing...)
First of all, any spell that requires an attack roll gets "No Save" at no cost. (That's actually the default.)
Transfer adds +3 levels. Improving from Touch to Close is +1/2 level. Dropping the effect to 1/2 caster level is -1/2 level.
So you could design a 3rd level spell that did 1d6 per two caster levels, transferring the damage to the caster.
Now just look at where we differ from this approach:
When comparing to Vampiric touch (a third-level spell), I felt the range upgrade (from touch to close) was worth about one spell level.
About 1/2, actually...
The dropping of damage dice to d4
Probably an adjustment of about -1/2...
and adding the fatigue effect...
Well, my research for Elves was based on 3.0 spells-- when there was no such thing as a fatigue effect. Considering that
Touch of Fatigue is a 0-level spell, I don't think the Fatigue effect should cost you more than about +1/2 level. It's actually probably a 0-level baseline effect (There's not a lot of room to reduce the level of Touch of Fatigue any more than 0-level because it's got nowhere "down" to go: Its range is touch, its duration is 1 round/level, so you've pretty much run out of the usual suspects for reducing a spell's level.)
But since we're combining effects into a single spell, +1/2 level is fair.
The only thing remaining is how valuable the "Jet" template is. I think the jury is still out on that one. The advantage of a spell that keeps on damaging is offset by the fact that the caster can't do anything else. Is it fully offset? Definitely not. Some kind of increase is in order.
EDIT: Hmmm... I'm thinking now of the "Repeat Spell" metamagic feat. I think it's in complete arcane, I think it's +2 levels, and I think it only lets the spell repeat once. My inclination with "Jet" would be to reduce the overall damage per round since you're spreading it out, which I think is more useful than giving full value for it but increasing the base spell level by 2 or 3 levels.
So I was looking at roughly a 4th-level spell. The difference is that vampiric touch is "one-and-done" while this one essentially lets you do it over and over and over (e.g., with a 9th-level caster, you're getting "9 shots" instead of the one afforded by vampiric touch). I felt that was worth bumping the spell up another level, though in retrospect, I think I the cap should have been bumped up with the actual spell level (instead of forgetting to adjust it and leaving it at third level's 5 dice). I guess it should be capped at 15 instead of 5 (since 5th-level arcane spells have a 15-die cap whether they are single-target or area-effect).
That's really the issue: there are certain expectations with regard to the damage cap.
But a 5th level spell is the point at which the game says you it's ok for you to be able to regularly KILL a target with a single spell.
Anyway, my favorite spell (flavor-wise) in this work was actually the "visionslur" spell. I'd love to hear what you think about that one, Wulf!
I'll try to get to that one next!
Wulf