Sithis

Tenet 1: Never dishonor the Night Mother. To do so is to invoke the Wrath of Sithis.
Tenet 2: Never betray the Dark Brotherhood or its secrets. To do so is to invoke the Wrath of Sithis.
Tenet 3: Never disobey or refuse to carry out an order from a Dark Brotherhood superior. To do so is to invoke the Wrath of Sithis.
Tenet 4: Never steal the possessions of a Dark Brother or Dark Sister. To do so is to invoke the Wrath of Sithis.
Tenet 5: Never kill a Dark Brother or Dark Sister. To do so is to invoke the Wrath of Sithis.


A creature of strangled, twisted shadow and spectral white bone that strikes an irrational, almost madness-inducing fear into those who gaze upon him. His presence alone is unsettling enough to cause those weak of will to hastily leave the place they encountered him in.
Sithis speaks few words, but his actions weave a tale of grief and bloodshed that span generations, dating back to when the Eleven first formed Sornieth. Was he a twelfth Dragon God that was scorned by the other Eleven? Some aspect of the Shade come to wreak havoc on the untouched world?
None know, but the assassins that follow him obey without question. Perhaps they fear asking.