Feathermanes are a tameable family of winged "hybrid" beasts, introduced in Patch 7.2. Members of the family include gryphons, hippogryphs, owlcats, wolfhawks and wind riders (also known as 'wyverns').
As a Hunter, how can I tame Feathermanes?
Feathermanes won't be immediately tameable to all Hunters - you have to earn the privilege! Here's what you need to achieve first:
You must have completed Power Ascended, which requires maxxing out all traits on the Beast Master artifact, Titanstrike, including those added in Patch 7.2, except for the final trait - you only require one point added to Concordance of the Legionfall.
You must have completed Breaching the Tomb, which is the Legionfall campaign for Patch 7.2. This is currently gated and can only be completed after the weekly reset on 06-07 June.
You must then complete a short scenario, Night of the Wilds, to earn your new Hunter class mount - the Loyal Wolfhawk. We're still unsure if that will become available after the weekly reset on the 06-07 June, or the week after.
What about my Hunter alts? Do I have to repeat this every time?
No! The Tome is Bind on Account. Once you've unlocked its purchase on one Hunter you may buy additional copies to send to your alts.
Are there level restrictions for taming Feathermanes?
You must be 110 to learn the ability.
Are there Hunter specialization restrictions for taming and using Feathermanes?
No. Any spec may tame and use Feathermanes, but to purchase the tome you must have advanced Titanstrike, which is the Beast Mastery artifact. This may take a little more effort for players who exclusively play Marksman or Survival. As noted above, this may be achieved through a different Hunter on the same account.
What happens after Legion?
It's highly unlikely that the ability to tame Feathermanes would ever be removed, though the method for learning it may change once Legion ends. We currently have no information on this.