This rune effect changes the damage type to poison, and causes the damage to scale up the longer a target is bathed in the rodent parade. As the  The tooltip for this skill is unclear. To clarify:The total damage from this one slowly rises to 220%, however, the damage also has the additional effect of lingering on the target even while [[Dire the Witch Doctor has finished casting. A quick spray of Plague Bats]] deals 220% right from the startwill induce a small DoT effect, it's not clear what the value while an extended spray of this skill Plague Bats will induce a more damaging, extended duration damage-over-time effect is.