A small light growing in illumination and size that shot out lights into a rainbow shaped illuminated area.

A oddly illuminated light moved slowly but inconsistently across the sky (bigger than any visible stars or planets) until it started growing in size and illumination.
It then shot out around 20 or more light beams at a 45 degree angle. Then a rainbow shaped slightly dimmer but much larger illumination appeared connecting all the light beams. At this point the whole thing took up about an inch or two of the whole field of view of the sky.
The origin point of the beams lost illumination until it wasn't visible while the rainbow shaped illuminated section persisted but faded consistently for a few minutes until it was gone.
It's worth noting I was sober and working the festival.
I saw it with atleast 7 other crew members and I heard chatter among the 6000+ person crowd throughout the night.