Demiplane Decay

If a demiplane is young and small enough, and the caster is powerful enough, demiplane decay has a chance to reverse a demiplane's growth, sending the demiplane into a slow but eventually cataclysmic decay. Large and established demiplanes (such as the Demiplane of Dread) are completely immune to this spell. However, the caster has a chance to affect a demiplane of an age equal to or less than his level in years. Thus, an 18th-level wizard has a chance to affect a demiplane 18 years old or younger; this mage would waste his time casting this spell on any demiplane older than this.

In order to affect a demiplane, the caster must use this spell while physically in the area in question. The actual casting takes only 1 round, but the mage must spend some time in preparation beforehand. Initially, the caster must spend 12 full hours on the targeted demiplane, contemplating the demiplane and mentally encompassing its breadth, nature, and specific qualities. If interrupted during this meditation, the caster must begin the contemplation anew. If any of the demiplane's natives know the caster's intent, they will likely try and interrupt the mage (with violence) during this time.

If the caster has the luxury of completing her contemplation, she can cast demiplane decay anytime during the 12 hours following the meditation. If any more time passes, the wizard must contemplate anew. Once a mage casts this spell, the demiplane makes a saving throw vs. spell as a wizard of a level equal to its age; thus, an 18-year-old demiplane saves as an 18th-level wizard. In addition, the demiplane suffers a -1 penalty for every year of difference between its age and the caster's level. For example, a 20-year-old demi- plane doesn't suffer a penalty to its saving throw when resisting demiplane decay cast by a 20th-level wizard. It does, however, suffer a -3 penalty against the same spell cast by a 23rd-level wizard. If the demiplane saves, the spell simply fails.

If demiplane decay is effective, a shudder passes through the entire demiplane, sending ominous zigzag cracks through permanent structures and causing anyone standing (if gravity exists in this particular demiplane) to make a saving throw vs. paralyzation or fall to the ground. The demiplane then begins to evaporate from the edges in a radius of 1 foot per day, as its essence bleeds into the surrounding ethereal vapor. The environment within a decaying demiplane becomes dark and charged with terrible storms, complete with high winds, hail, and terrible displays of lightning. As the edges crumble away, residents and structures that can't make the leap to the Border or the Deep on their own melt into the surrounding ethereal mists.

Mobile natives and stranded visitors can delay the inevitable for some time by moving to the "center" of the demiplane, but eventually the decay eats its way into the final heart of the aborted plane until all finally boils away into a fading memory.

The material components for demiplane decay include any artifact worth 1.000 gp or more from an extinct race, civilization, or plane (possibly even a demiplane upon which this spell was successfully used in the past!).