Ghostwalk Crystal, Greater (3.5e Equipment)
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Greater Ghostwalk Crystal: This clear sphere looks to be filled with a pale green mist.
These augment crystals were first crafted by the elves of a bygone era in order to aid them as they patrolled their woodlood homes. A ghostwalk crystal cannot be applied to medium or heavy armor or to shields, and all benefits are temporarily lost when carrying more than a light load.
As the lesser crystal, plus when moving, you become nearly incorporeal and can ignore the effects of difficult terrain. You can even move through an enemy’s space, but not through walls or other solid barriers. Furthermore, any attacks of opportunity directed at you while you move have a 50% miss chance. You can suppress or activate this ability at will as a free action even when it isn't your turn, you gain the crystal's benefits instantaneously.
Faint (DC 17) evocation;CL 9; Craft Magic Arms and Armor, ethereal jaunt, expeditious retreat; Weight: 0 lb.; Market Price: 17,000gp