It seems this latest PTR build has revealed some interesting knowledge about the reward for the next part of the legendary questline - ilv600 cloaks! A massive increase over current gear... and if the item level wasn't overpowered enough, they all have 3 sets of secondary stats instead of the usual 2.
If that's still not enough there's hints they may possibly be upgraded even further, not only via the normal valour upgrade, but through the questline as well!
As you can see there is a somewhat plain version and a kind of "empowered" version of each, so we can speculate that we'll start off with the base epic version then eventually upgrade it to a more powerful (perhaps legendary) version.
Oh and btw, the ilv600 one appears to be the base epic version, not the upgraded one! These cloaks are looking to be extremely powerful items.
Jadefire Drape
Oxhoof Greatcloak
Tigerclaw Cape / Tigerfang Wrap
Cranewing Cloak