A set of Morse Code posted at the bottom of the D&D Twitch stream promoting the Stream of Many Eyes event in Los Angeles in early June. It was soon reported by several people on Twitter.
"Morse Code at the bottom of the page reads: #NoStoneUnturned@JasonTDnDDm:
Clever! Wonder if we'll see more hints?!? #jocksmachina #criticalrole" - @shandravdeg, 5/1 @ 1:58PM
"T'would appear that,
# -. --- / ... - --- -. . / ..- -. - ..- .-. -. . -..
Found at the bottom if the DnD live stream announcement for the new adventure, translates from morse into "No stone unturned"...
A reference from "Eye of the Beholder" in Undermountain... MEGADUNGEON!!" - @JasonTDnDDm, 5/1 @ 6:23PMThis also revealed the hashtag used throughout the game, #NoStoneUnturned.
The first post on the @immortal4tress Twitter account was a few hours earlier:
"To expedite the artifact's return, we'll heed the trail and leave #NoStoneUnturned." - @immortal4tress, 5/1 @ 4:45AMThe adventure officially began by several posts on the Wizards of the Coast D&D Twitter account by a mysterious individual, posted on 5/2:
"Forgive my usurpation of this information stream, but circumstances call for nothing less. I dare not cede control ere I’ve occasion to recount a brief but dire missive from the realms that time forgot."
"The Sage of Shadowdale hath hid on Earth a stone, of power great and imminent import. Its guardian, an exile from my realm, was spirited to Earth with this in tow; To keep it safe and secret ere its prophesied return."
"The hour of its need now soon at hand, this item and its wielder must be found; Sent, via portal, back from whence they came. At long last, well and truly homeward-bound."
"The Sage of Shadowdale himself is otherwise engaged, and cast me as his proxy in this search. Unable, as I am, to sojourn there myself, this task falls to the denizens of Earth."
"Should you be of a mind to render aid, direct your queries to mine own account. I’m called @Immortal4tress, my address: your internet; Elminster’s humble servant, and forever in your debt."
- Full thread from @Wizards_DnD, 5/2 @ 1:33PMThe website immortalfortress.com, refenced by the above Twitter account, initially contained a cryptic message and symbol, which was posted by @mrSmfwic on 5/3. The website was blank at first, but only visible if you "select all" in your browser.
"Took this screenshot from http://immortalfortress.com #NoStoneUnturned" - @mrSmfwic, 5/3 @ 11:29PMThe website has since been altered to be what it is now, a place to report all the findings.