Ring of the Reefs

Simply Turn in at Valdemar Stormseeker In Stormheim (Legion Content)

Seems like Completion part is not added on Wowhead, here it is:

Spoiler

Completion
Another ring? Hmph. Yes, we have been seeing them more frequently.

<Valdemar grimaces.>

Helya is growing in power.

What, small one, are you surprised? Did you think she was defeated?

<Valdemar laughs heartily.>

You cannot kill death!

I thank you for making me laugh today, little friend.

Odyn has heard about your search for Azerite, we have gathered what we could.

Here, it is yours.

(According to that, my own lore speculation here)

Spoiler

"You cannot kill death!"

So, it seems Helya is alive and well!

This may be one of the first signs that Battle for Azeroth is going into a Shadowlands direction, but not sure how it will be, will it be a patch content or an expansion?

Now, all I sense is:
- The Sylvanas-Helya dialogue may continue.
- Rastakhan has linked his bloodline with Bwonsamdi that may have some continuation.
- We know Vol'jin is bro-mode with Bwonsamdi already.
- And our current Lich King Bolvar may easily be linked with his recently revealed daughter Taelia Fordragon and through her, Anduin and Alliance.
- As a bonus, we have Calia Menethil and her unusual resurrection...

I guess we'll wait and see!

You know...
Hype? :>

The return of Helya, I admit, I did not foresee. Most likely she is so connected to the Shadowlands that when we killed her, she regenerated within it like a demon regenerates in the Twisting Nether. However, her bond trapping Odin in the Halls of Valor, and maybe the Kvaldir as well, was broken. But it seems she regained control of the Kvaldir after she reformed. There is also evidence that the Wild Gods do this as well.