Dragon #353 Spellthief Substitution Errata

[Armitage]

From Cursed Blow:
"The curse places a penalty... equal to the level of the spell slot expended... with a successful save reducing the curse's penalty to -1 per level of the spell slot."

So expending a 3rd-level spell would create a -3 penalty, or a -3 penalty if the save is successful.
That certainly can't be right.

[Magagumo]

I've been puzzling over that myself, and believe they meant to say, "This ability applies a penalty of X to a, b, & c, where X is the level of the spell slot expended. If the target makes the save, then the penalty is reduced to X-1"

Thus, a 1st level spell slot can be negated to a nonexistent penalty, but the use of a 4th lvl spell slot will still result in a -3 penalty.