Asgard II was a base built by the remnants of Valkyria, the Legion, and others (or the "Asgard II Group" if you don't have the time) during the Second Valkyrian Period. It was the next project after Fenrir and it was a base that had a population of 30 players.
"There has never ever been closure on what happened at Asgard II" - Fit, July 25th, 2016
The griefing of Asgard II has been a convoluted and debated story. Many stories have been made speculating the destruction of Asgard II. Some people claim that OreMonger was responsible for the greifing due to an anonymous person with an alternate account leaking the coords, who was suspected to be a spy at the base, others believe that it was leaked by Sato due to internal struggles between James_Rustles, xarviar, Sato, and many other known kikes building at Asgard II, some believe their was an exploit used to find it, and many other stories of the like have been told. Controversial as the greifing is, the news of the public leak caused the residents to panic, some fleeing, others blowing up parts of the base so that no one could claim to have destroyed the base.
After the grief however, the members became angered at the destruction and the third incursion began on April 29th, of 2015, two years after the founding of Valkyria, and lasted through the whole month of May, in revenge for the destroyed base. After the Incursion, the idea of Valkyria eventually began to dissolve and eventually was forgotten.