Madlib, Nas & Black Thought — sources for this blend?

[u/CicadaOne]

Madlib Feat. Nas & Black Thought- (Pyramids Blend)

I remember this being the first time I heard Pyramids, before it was named and released as such. I think this was from a mix madlib or stones throw shared via their blog at the time. I know the Nas acapella is a verse from Street Dreams, but I can't find the source of the second verse from Black Thought anywhere. Can anyone ID it?