Here it is: Left 4 Dead's No Mercy rooftop finale, now for CS:GO!
I made everything from scratch, using the L4D map as a reference. There was no porting of any content or copying and pasting.
This version of the map features 10 spawns, buy zones, and one bomb site.
Other features include rain, sounds, lightning, optimization, cubemaps, color correction, and a custom bot navigation mesh.