A black ray of crackling negative energy suppresses the life force of any living creature it strikes, giving an enemy 1 to 4 negative levels and applies a stacking damage over time effect for 1d6(+2 per caster level) negative damage. Stacks up to 5 times. If the target has as many negative levels as its hit dice or levels, it dies. Each negative level gives a creature a -2 penalty on attack rolls, saves, skill checks, ability checks, and effective level. Negative levels stack. As a ray this spell has double range.