in theory good but in practice the engine make a short circuit. <- my synonym for loops
there is a optimize.map
if u hit the key 1,2,3,4,5 it start the zomie with one follow call and the frame rate drop very much.
the framerate without zombies seems also abnormal low.
with sync false is it ~70 frames.
https://drive.google.com/open?id=0B942ivL2fTGcQ0E1Zkc2ZDdhX1U&authuser=0