So, to resume the events chronologically :
- BC Period : Illidan plans to assault Mac'Aree (Kil'Jaeden's palace) on Argus using Sargeras Keystone after the discovery of the planet's coordinates on Nathreza.
- BC Period : Illidan sends his Demon Hunters on Mardum to steel the Sargeras Keystone.
- BC Period : Illidan is defeated at the Black Temple and the Demon Hunters come back successfully from Mardum. They are caught by A'dal forces and brought to the Vault of the Wardens by Maïev Shadowsong with Illidan's body and the Sargeras Keystone.
- WoD Period : Cordana Felsong, the Warden, falls under AU Gul'dan's control and joins the Shadow Council.
- WoD Period : AU Gul'dan succeed to take control of the main part of the Iron Hord that is standing in Tanaan Jungle.
- WoD Period : Before that success, Archimonde is sent by Kil'Jaeden to take the lead and prepare an invasion of Azeroth.
- WoD Period : Archimonde is killed by Draenor Heroes and sends AU Gul'dan to the Twisting Nether where other plans are waiting for him.
- Between WoD and Legion : AU Gul'dan is told about Illidan, the Pillars of Creation, the Sargeras Keystone and is briefed to prepare another Invasion.
- Between WoD and Legion : AU Gul'dan is sent to Azeroth with an army of demons to assault the Vault of the Wardens with Cordana Felsong's help.
- Between WoD and Legion : Maïev Shadowsong comes back to the Vault of the Wardens and witnesses the Legion's assault there.
- Between WoD and Legion : Maïev Shadowsong free the Demon Hunters and tell them to stop Gul'dan before it's too late.
- Between WoD and Legion : AU Gul'dan and Cordana Felsong get the Sargeras Keystone and Illidan's body and flee.
- Between WoD and Legion : Maëiv Shadowsong tells the Demon Hunters to find Kadghar.
- Between WoD and Legion : Magni Bronzebeard is awaken from his long sleep by Azeroth and starts to warn the Dwarves and alliance about the Legion's threat.
- Between WoD and Legion : AU Gul'dan uses Sargeras Keystone to open a huge gate to Argus at Tomb Of Sargeras location in the Broken Isles.
- Between WoD and Legion : A large Legion invasion begins all over Azeroth.
- Between WoD and Legion : Kadghar alerts Varian Wrynn about the Legion invasion located in the Broken Isles.
- Legion Period : Factions leaders call their heroes to attack the Broken Shores and push the Legion back.
- Legion Period : Factions are defeated and are back to their capitals, grieving their leaders and heroes.
- Legion Period : Kadghar summons you in Dalaran, that is relocated near Karazhan, to help him to introduce Hord into the council of Six. Brann Bronzebeard appears and invites you to Ulduar to speak to Magni Bronzebeard
- Legion Period : Magni Bronzebeard tells you about the Legion's threat and the Pillars of Creation. Then Kadghar is teleporting you to Karazhan to find informations about their location.
- Legion Period : In Karazhan, you find out that these Pillars are in the Broken Isles
- Legion Period : Kadghar summons you in Dalaran because the city is attacked by the Legion. You help him to relocate the city in the Broken Isles.
- Legion Period : Meanwhile, AU Gul'dan launches repeated attacks over Suramar to access the Nightwell, the most powerful source left on Azeroth.
- Legion Period : AU Gul'dan succeeds to enter Suramar and starts to use the Nightwell.
- Legion Period : Kadghar summons you to Dalaran in the Broken Isles and then start the Artifact & Order Class Hall questchains and then the leveling quests.
- Legion Period : You enter the NightHold in Suramar and finally fight Gul'dan that is using the Pillar of Creation located here, the Eye of Aman'Tul to summon Sargeras' soul into Illidan's body.