Yay! This was out of an Emissary Cache. And I really have lost count of which legendary it is - it's the last resto one though (if you don't count Amanthul's Vision).
This one is pretty cool, and I think it would be good for raids. I gave it a whirl last night in Mythic + but I don't think that I really like it as much as I like Soul of the Archdruid.
So that puts me at... 27 legendaries. And I still have 8 more to go! I wonder if I can get them all by the end of the expansion?
Behemoth Headdress
Elize's Everlasting Encasement
Ailuro Pouncers
The Wildshaper's Clutch
Skysec's Hold
Dual Determination
Archimonde's hatred Reborn
Aman'Thul's Vision