Here's an interesting situation that can come up with Stoneskin:
You take enough damage that the amount the spell can still take is something less than 10 (let's just call it 1). On the next successful attack, how much does Stoneskin prevent?
A) One point, because it discharges after taking that point of damage.
B) Ten points: You have DR 10 before the attack, and it cannot be discharged after the first point but before the rest of the damage.
C) Other?
For reference:
You take enough damage that the amount the spell can still take is something less than 10 (let's just call it 1). On the next successful attack, how much does Stoneskin prevent?
A) One point, because it discharges after taking that point of damage.
B) Ten points: You have DR 10 before the attack, and it cannot be discharged after the first point but before the rest of the damage.
C) Other?
For reference:
SRD said:The warded creature gains resistance to blows, cuts, stabs, and slashes. The subject gains damage reduction 10/adamantine. (It ignores the first 10 points of damage each time it takes damage from a weapon, though an adamantine weapon bypasses the reduction.) Once the spell has prevented a total of 10 points of damage per caster level (maximum 150 points), it is discharged.