Blizzard has previously promised that World of Warcraft's

Kosumoth (massed protectors of Azeroth for scale).

Members of the Wowhead community - searching for the Reins of the Long-Forgotten Hippogryph item that should unlock an unreleased Mount that was last seen back in 2007 - discovered a set of well-hidden caves (for reference, "hidden-in-the-middle-of-the-ocean-behind-some-kelp-inside-a-hole-inside-a-sunken-ship" levels of hidden) with mysterious orbs inside.They then discovered that the cluttered table next to a specific NPC was actually a makeshift map of the Broken Isles region, marking the position of ten orbs, which had to be activated in a specific order.The group painstakingly found them, worked out the order and activated them and - instead of a nice Hippogriph turning up - a gigantic Old God called Kosumoth the Hungering appeared on an otherwise unused island, after which the game asked every player around, regardless of faction, to go kill it. Here he is:If you want more detail, Reddit has a good summary of how Kosumoth came to be . Players who complete the lengthy quest are rewarded with either a Fathom Dweller jellyfish mount or a Hungering Claw tentacle battle pet - i.e. not the item they went looking for in the first place.Tantalisingly, the hunt for the Reins of the Long-Forgotten Hippogryph is back to square one - who knows what that secret will turn out to be.If that isn't enough to intrigue you give Legion a try, perhaps our glowing review-in-progress will help. Blizzard's had a pre-occupation with secrets recently it seems, what with Overwatch's Sombra ARG still torturing the Internet's codebreakers.

Joe Skrebels is IGN's UK News Editor, and he's now broken enough to think this might be a Sombra clue in itself. Follow him on Twitter