Holy shit! The new lore on ESO Markarth shows us that Rada-Al saran and Count Verandis are among most powerful vampires in fiction. They both tapped into the Dark Heart, an inverted version of Heart of Lorkhan that grants godhood. Voidlike Godhood that has the direct connection to Sithis. The Heart draws power directly from the Void that Padomay controls. Namira was born from the Dark Heart, and she was considered as a Ur-Dra as Nocturnal. Both Nocturnal and Namira were born from the Dark Heart; thus, they are twin siblings.
The Dark Heart, also known as the Frightful Heart,[1] is an artifact associated with Namira through some of the cultural interpretations of Lorkhan, specifically Lorkh and Lorkhaj. Physically appearing as a sphere of darkness surrounded by a radiant aquamarine corona, it is a piece of primal...
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The power of Namira or anyone who controls the Dark Heart is the power from the Void beyond all Aurbises, and no wonder why Namira doesn't give a **** about Daedric affairs because she potentially can drop-kick anyone of them if she fully uses the Padomaic powers from the Void. Like Nocturnal did.
Meridia persuaded her angry Et'Adas to punish Lorkhan for his treachery. The neutral Riddle'Thar also played an important role of guiding the dying Lorkhan to Azura who purged the corruption in the hole in his cosmic chest. Apparently, Azura was Lorkhan's mistress who allowed Lorkhan to safely pass on without any corruption of his spirit.
Rada-Al saran was desperate to get the power of the Heart, so he can be free from Molag Bal forever. Additionally, he and the Gray Host will gain profound power to attack and destroy any cosmic realm or god at their likings. The reason is that their realm, created by the Dark Heart's power, is beyond Aurbis that no one can reach. Not even Magna Ges, Aedras and Daedras can reach it. For a brief moment, I would say Rada is at High 1-B level. He later was defeated by the badass Vestige and tricking Verandis. The Count Verandis used the Dark Heart to betray Rada-Al saran, and casted both the Heart and himself into the unknown Void eternally. Verandis, tangled with Dark Heart, became the godlike guardian who is now drifting endlessly in the Padomaic Void.
Final Verdict: Verandis and Rada Al-saran are at High 1-B.