Did they ever explain

[Benedikt-emerald-dream]

We do see chains similar to what was in the cinematic in use there. At the time it was a /shrug because sure why wouldn’t they have spooky chains?

But in retrospect I think it’s actually not a bad tease at what comes next. Amadis detailed this more in a post I’ll quote here.

@Amadis-draka

However, it dawned on me that there was perhaps even more support for this all along, we just never would have suspected it. During the Alliance side introductory questing to the Darkshore Warfront, the Val’kyr stun the Alliance player and Tyrande. With the following affect:

The Val’kyr use chains covered in dark purple energy. There is even a clinking sound of chain-links rattling together that is heard during the ability. This ability is called Umbral Biding, and makes the edges of the Alliance player’s screen wick with dark purple energy while stunned by it:

But, yeah this actually seems more like a tease for SL than blatant lore abuse with that in mind. I’m not in the habit of giving Blizz good faith here and people weren’t wrong to just assume it was a plot hole. But - doesn’t seem like it was with that in mind.