The hunt's over: all 6 of Diablo 4's mega-rare items have been discovered

pcgamer.com:

Diablo 4 players can finally rest easy—that is, unless they're trying to farm these pieces themselves—as the last of Diablo 4's six elusive super-rare items has been found. As spotted by AnyComputer on the Diablo 4 subreddit, the final piece of the collection was The Melted Heart of Selig. It dropped for a Chinese necromancer player in the Blind Burrows, a dungeon that can be found in the Hawezar region of the map.

The Heart's effect isn't that exciting, unfortunately. It gives a substantial boost to your class's resource, but turns it into a pseudo-barrier, draining 3-8 of your resource for every 1% of damage you would've otherwise taken. 

That 3-8 variable is massive: if your character took 10% of its life in damage, for example, a roll of 3 would drain 30 resource, while a roll of 8 would cost a whopping 80. Even if your build can jive with dumping its resource for defence, this item's power, like many in Diablo 4, is entirely down to RNG. Still, if you've got a funky build that doesn't spend its resource on anything else, the Heart is an obvious add (or would be if you stood any chance of getting one).

If you're curious as to what the other treasures do, PC Gamer has a full list to explore, though we recommend tempering your expectations—even if you do get one to drop, a low roll on a key affix could just make them salvage fodder.

This marks the end of a long hunt for these items, one that's been raging since Diablo 4's Lead Class Designer Adam Jackson revealed them in a tweet last week and sent players on a wild gear chase across Sanctuary. Of course, now that they know where each item can drop, the pie-in-the-sky theorycrafting can begin, though your chances of actually bagging one remain small.