The giant water serpent

Date: 8/7/2023

I was in some some type of building like an office building I think and there was a lake out in front of it. There was two floors in this building and the bottom floor was underwater and also this building had these large glass windows even in the basement. I was looking out the window on the first floor which was like a lobby area, i talking to someone when I saw off in the distance this giant snake or maybe it was a dragon that was twice maybe three times the size of the building I was in, this thing was super fast and caused enormous waves as it circled the building multiple times, it would go right up to the side of the wall close to where I was standing causing giant waves to crash over the side of the building . We went into the basement to get a better look of it. There was an office downstairs so me and this person stood outside the glass wall of this office and looked beyond the person at their desk talking to a client to see the serpent passing the window completely underwater. The people at the desk seem completely unaware of the giant serpent that was outside the window even the person who was facing the window did not seem to be aware of what was going on the person behind the desk looked at me and the person who was standing outside of the wall/door with a strange look like "what what are you doing?"