How to start the Allied Races quest line

First you must complete these requirements;

Need to have purchased Battle for Azeroth
Have a level 110 already on that server
Highmountain Tauren
Exalted with Highmountain Tribe and completion of Ain't No Mountain High Enough.

Nightborne
Exalted with the Nightfallen and completion of Insurrection.

Void Elf
Exalted with Argussian Reach and completion of You Are Now Prepared!

Lightforged Draenei
Exalted with Army of the Light and completion of You Are Now Prepared!

After that

Head to embassy in Orgrimmar or Stormwind
Talk to ambassadors for traist and requirements
Talk to Anduin (alliance) or Sylvannas (horde) to start the scenario

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