The daedric princess known as Mephala (also known as Webspinner, or spider god) is looking to spread her dominion of terror from Morrowind into Skyrim. But the increasing presence of the Dovahkin is giving the common people hope and proving a hindrance to her. Thus, using her demonic guile she has bent the will of many of her enslaved victims and her daedric followers have trained them to become the ultimate assassins. Granting the enslaved souls the ability to metamorphose into a person they can vividly visualize, she has a vast army of doppelgangers, which are highly skilled in the art of back stabbing (silent kills).

The unholy Mephala Assassins dwell among the populace and when the time is ripe attack their target, often being able to walk right up to the victim undetected until it is to late to avoid the fatal blow.

When visiting an area full of people, the Dovhakin will now need to keep a careful eye out. The doppelgangers have the ability to look like anyone in the vicinity and will not set off alerts when walking about. Further, they will not strike instantly, but rather try to preform a sneak attack from behind. Only then will the player know that the old grandma he just saw was in fact a deadly enemy.

To ensure the job gets done right, Mephala has also trained hunter assassins to seek out the Dovhakin in the wilds. They are less likely to be able to pull off a successful sneak attack as their brother within a city, so they will become aggressive and show their true intentions more rapidly.

To guarantee a quick kill for these advanced assassins, Mephala has armed them with the most deadly of poisons--known as Mephala's Kiss. This poison strikes the core and renders the victim paralyzed for a short amount of time. During paralyses, the poison seeps into the victim's blood veins which gives it a direct (and rapid) path to the heart--causing almost immediate death. Once poisoned, by Mephala's Kiss, the victim has only a minute or two before they die. Both cure poison and cure disease potions can cure the victim and must be taken quickly to avoid succumbing to an agonizing defeat. Fortunately, if an adventurer defeats one of these assassins, these rare weapons will be available to use and/or sell.