War of the Ancients
At the beginning of the first war against the legion, Korialstrasz became incredibly and inexplicably weak.
The cause, which Alexstrasza later determined, was Korialstrasz's future self, Krasus, existing the same time period as a result of being flung back from ten thousand years in the future (See Modern Era section below). Neither incarnation was able to shape-shift during this time. After being rescued from Cenarius' glade, Krasus was brought to Life Caverns, home of the Reds, where he was united with his past self. Despite great temptation, Krasus refrained from revealing any future events to anyone, even his queen, from fear of radically altering the future. Aided by a vision from
Nozdormu the Timeless One, the younger and older Korialstraszs then teamed up to find the young druid Malfurion Stormrage, eventually joining the night elf resistance to the Burning Legion's invasion. Often, while Krasus led the night elf spellcasters, Korialstrasz would either aid the host from above, raining fire down on the demons,
or rally some sort of surprise ally. Both Krasus and Korialstrasz fought valiantly against the likes of Hakkar the Houndmaster, Mannoroth the Destructor, Archimonde the Defiler, Sargeras the Destroyer, and their twisted former friend and allies, Neltharion the Earth-Warder and his Black Dragonflight. After escaping the Great Sundering of the Well of Eternity and the legion's defeat, Krasus
and his companions were returned to their own time by Nozdormu.