This spell is the reverse of Cure Serious Wounds. Instead of healing the creature touched, it causes damage. On a successful touch from the priest, the spell inflicts 17 points of damage upon the target. The next attack that the priest makes will inflict this effect, however, [they] only have 2 rounds to make the attack before the spell fizzles. If the priest misses the target creature, the spell is wasted. There is no Saving Throw.
Cause Serious Wounds works like any other spell which conjures a weapon, such as Shillelagh or Flame Blade. The primary difference is that it has a much shorter duration and that the conjured "weapon" disappears on its first attack, even if it misses the target.
The conjured weapon deals 17 magic damage, has a -2 THAC0 bonus, and has a speed factor of 1. It does not have a proficiency class, meaning it does not gain any benefits nor does it impose penalties based on proficiency.
It strikes as a +6 magical/silver/cold iron weapon.
Because the damage is dealt as weapon damage, it bypassess magic resistance; however, magic damage resistance (such as the kind granted by Armor of Faith) still applies normally.
Like all spell-created weapons, if a character dual-wields while Cause Serious Wounds is active, their off-hand weapon will not suffer any off-hand THAC0 penalty. This is of limited use, however, given the extremely short duration.