Conversation so far:
what is vortexx I?
"Vortex I: A Biodegradable Festival of Life," in imitation of the famous Woodstock Festival held the previous year.
was this popular?
Vortex was the first and so far only state-sponsored rock festival in U.S.
history.
was there problems having it commence?
The festival, nicknamed "The Governor's Pot Party" by Oregonians, was a success, attracting between 50,000 and 100,000 people.
who led the festivle?
Milo McIver State Park near Estacada.

Question: who played at the festivle?
Self-contained rewrite: who played at the festival vortexx I?