So, Chris Barrett tweeted this this morning:

Link to Tweet

As far as I know, the Seven Seraphs haven't been mentioned in an official capacity since... before Destiny released?

Excited for some Osiris action in Des2ny. Maybe the story will actually involve the speaker this time!

As far as I know, the Seven Seraphs haven't been mentioned in an official capacity since... before Destiny released?

Actually, it was also mentioned during the Cosmodrome ride along that the Seven Serephs were a group who build Rasputin's Serephim Vault.

Then, there's the Grimoire card Lord Timur. It implies that some Exos might either be Warminds or be controlled by them:

You seem far too obsessed with these ‘Warminds’.” Timur stops and stares into the horizon as if smelling something; not danger, discovery. He draws his fellow Iron Lord close. “Tell me, Felwinter,” he whispers, “what does the word Seraph mean to you?”

Exos being controlled by Warminds would fit with four Ishtar Collective scientist Maya Sundaresh and her wife Chioma Esi, along with Duane-McNiadh, and Dr. Shim returning to a Vex structure in the form of "biomechanical proxies" with their thoughts firewalled and passed through a Warmind to keep them safe from Vex interference. (Ghost Fragment: Vex 4, See also: The Exo Stranger, Founder of the Future War Cult?)

Also, our ever present Clovis Bray was involved:

"With all respect, Lord Timur, whatever game you are playing with me has gone on far too long. This is just another Dead Zone."

"Oh, is it?"

Timur directs Felwinter's eyes towards the eastern horizon, where a building crowned with the initials "C.B." is now in view.

"We all have creators – humans, Exo, Warminds, even those poor Awoken. Some are just easier to find."

Let's just say I can't wait to really dig in to the story of the Iron Lords! :)

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So, Chris Barrett tweeted this this morning:

[img]

The true origin and meaning of the 7 Seraphs can be found on ,,,2;;:66~3&&: *end transmission*

[Seven Seraphs Image]

Link to Tweet

As far as I know, the Seven Seraphs haven't been mentioned in an official capacity since... before Destiny released?

Based on other Tweets and Reddit posts, this looks to maybe just be a troll tweet?
Chris Barrett and Deej appeared on the 100th Episode of IGN's Fireteam Chat. The IGN host (Destin Legarie) brought up Seven Seraphs again like he says he has many times before in the past.

http://www.ign.com/videos/2017/02/11/59-destiny-concepts-you-need-to-see-igns-fireteam-chat
Go to Time Stamp @ 29:45

I don't watch this IGN show, however, they seem to have been privileged to be host to the revealing of some never before seen Concept Art. I could be mistaken but a number of the images Chris shares I don't think have ever been revealed before. (A few have been seen in the Art Of Destiny book, Developer Conference Presentations, or other online repositories)

There is a prior Tweet from Chris that may or may not be related, from Oct. 2015:

I forgot about this old emblem I made. I still have the shirt around somewhere... K" J+ J+EFK+=+LJ.?LC+;CL.
[Seven Seraphs image]

^ Older Tweet may have happened after a prior appearance on IGN's show? Or run in with host Destin?