As I learned the primary design difference between Buran and the USA Space Shuttles was that Buran rode a rocket to the orbit passively, while the Shuttles were firing their own engines, riding on huge passive fuel tanks, I didn't pay much attention as to what engines Buran had. "Just RCS" was the easy dismissal.
Then I saw this:
Could someone explain what I'm seeing here? Looks like at least four types of engines. I can guess the RCS blocks and jet engines for atmospheric test flights... and the rest?