rift item:Guise of Death  

When used, shrouds you in the guise of death. Your guise will vary by class. The trinket can be unequipped after casting and keeps its form. Form has no time duration, persists through death and won't allow you to mount. Taking damage or casting skills won't remove the form and using the shade aura will make its eyes glow.

River of Souls World Event Rift: Patch 1.1