Original Link (now dead) -http://www.zone.com/asheronscall/ASHEnimbus.asp
Nimbus of Many Colors
A diligent adventurer lays steel to his monstrous foe, and as it topples, a rising hum suffuses the air. A rainbow-hued nebula swirls all about, and cascades upward, then fragments and dissolves as the hum itself breaks in a fading tinkle as of distant chimes. Something has been achieved, but what exactly, and who or what deigns to recognize it?
Scholars are divided in their speculations. A small faction suggest that the nimbus is life energy that one absorbs from his or her stricken foe. Usually this energy goes unnoticed, but every so often it accumulates to a certain threshold, compacts itself, and gives off light and sound just as compressed air gives off heat. This theory, however, does not explain why a person's resurrections become more tiring after a nimbus first appears. Therefore, most scholars hold that Asheron's magic is responsible.
Asheron has a grip on the life energy of all humans in Dereth, the only beings visited by the nimbus. Did Asheron design the nimbus, or is it an incidental effect of his resurrection spell, which drains more life energy as an adventurer becomes more powerful? Perhaps Asheron taxes each according to his or her ability to pay, and either consumes the energy or stores it for some great task.
As Asheron has not come forward to offer reassurance, scholars fret about the eventual human consequences of his plans. Until more is known, they implore you to avoid death as scrupulously as possible.