Full: Create a level 1...8...10 spirit. When any non-spirit creature within its range dies, conditions on that creature spread to any creature in the area already suffering from a condition. This spirit dies after 30...78...90 seconds.
Concise: Creates a level 1...8...10 spirit (30...78...90 second lifespan). When any creature in range dies, conditions on this creature spread to any creature in the area with a condition. Spirits are not affected.
If you can stack a pile of conditions onto an allied minion, with Infuse Condition, for example, you can kill the minion with Taste of Death or Putrid Flesh while it is under the effects of this skill to create little plague-bombs. Unfortunately, putting conditions on allies is difficult. As such, try combining Infuse Condition with Draw Conditions or Martyr.