Expansions

The Burning Crusade

This expansion was all about the return of the "Burning Legion" who are an army of demons. A Doom Lord who was called Kazzak, had opened a Dark Portal to Outland, which flooded Azeroth with demons, which both the Alliance and Horde had to fight, and had taken their fight to Illidan Stormage (Character in gif).

Wrath Of The Lich King

After fighting the "Burning Legion" an army of undead Scourge had launched attacks at various cities and towns within Azeroth, both the Horde and Alliance sent their armies to Northrend, a frozen continent. There both armies would face a dangerous enemy The Lich King.

Battle For Azeroth

After the 'Legion' expansion, which meant the return of the "Burning Legion" led by a Orc called Gul'dan, who had threatened Azeroth, who had all been defeated by the Horde and Alliance. Both factions fell back to their old ways, being at war with each other, which had started after a precious resource called 'Azerite' which contained extreme magical power, had been found by the Goblins of the Horde. Both Factions craved this resource and began to fight over it, leaving Darnassus, home of the night elves annihalted, along with Lordaeron, home of the Forsaken, obliterated.