Opinion: Living Shadow should be a trait that replaces Darkside.

[Otorinth]

Comparing video content Living Shadow doesn't appear to be random. In every video the same sequence of abilities was used in the same order.

Abyssal Drain, Plunge, Quietus, Flood, Edge, Blood Spiller, Carve and Spit.

That gives a ratio of 3 AoE abilities to 4 single-target with an ability used approximately every 2s during the time the shadow is active (~15s).
The potency for each ability is likely to be predetermined and set to something independent of what the player has as the potency for those abilities.

I could see it being something like
100-100-100-300-200-200-100 which would be 1100 potency to a single target and 400 potency of AoE damage. That would be almost like 2 Bloodspillers and 2 Quietuses in one for the same cost as just one of those abilities.

From what I've read, with maximum up-time, it will do 7 attacks all doing the same damage at what seems to be 400 potency, totaling out to 2800. Pretty spicy for a 2 minute cooldown and only 50 blood.