It’s back! The sword-that-is-an-axe hidden artifact appearance has returned to both Remix and Retail. Warriors can grab the rare quest that seems to randomly appear in their Order Hall today on US/OC realms, so head on in there and roll a new Warrior if you need to!
Strom’kar, the Warbreaker is about to get very Axe-y for a lot of Warriors, as the hidden 
Arcanite Bladebreaker appearance is available today, so hurry! Head to your Legion Order Hall and grab the Secrets of the Axes quest from Master Smith Helgar (he’s over by the Forge of Odyn), and he will give you a quest where you must duel Saurfang to earn the hidden appearance. The quest is up for around a day, as spotted by JRocksMyLyfe around 5 hours ago as of this writing.
You’ll need to have the Arms artifact unlocked, but it’s actually worth rolling a new Warrior and going through the Remix/artifact intro, as the quest comes around relatively infrequently. To top that off, once Remix ends, there will be far fewer players checking in on their Warrior Order Hall, so far fewer of these types of heads up as well. Here’s a video with all the details.