This spell allows caster to make a successful melee attack to reduce target hit points to 1. The caster has 2 rounds to make this attack before spell duration expires. If caster attack misses, the spell will stop working as well.
To maximize the chances of success, the caster should have a good THAC0. It is therefore best used by a multi- or dual-classed caster. Multi-classed Fighter / Druids, Fighter / Clerics and Cleric / Rangers can achieve 100% success rate by using the Critical Strike High-level class ability in combination with this spell.