Nightfall Skyreaver

Descending on their prey in the dead of night, the cries of these skyreavers once instilled terror in all the children of Draenor.

Riding Requirements:

This mount is available to all eligible characters on your account.
Level 10
Apprentice Riding (ground)
Expert Riding (flying)

Source:

Tempra in Stormshield.
Kronnus in Warspear.
Cost: 5000
Only available during Timewalking

Notes:

Added in Patch 11.0.7 as part of a Timewalking rewards update, this armoured black rylak can be only purchased during Warlords of Draenor Timewalking events. Purchase requires Timewarped Badges, which are earned by running Timewalking Dungeons during the events, with a bonus 500 by handing in a quest item which drops at the end of your first dungeon for the event.