Players begin at 0/36000 hated with Netherwing, and must be exalted to obtain a Nether Drake mount. The quest chain/reputation grind is a mostly solo endeavor involving daily quests, one 5-person group quest on the way to neutral, and a daily 3-person group quest once reaching revered. A flying mount is required for this reputation grind, and 300 riding skill is necessary to advance past neutral. Netherwing is one of the only factions in the game where players do not lose reputation by attacking and killing its members.
Netherwing dragonflight - WoWWiki - Your guide to the World of Warcraft