Every easier boss addon + synchronizer = Biggest glitch ive seen, you shoot one bullet at a boss and they (mine bieng slime boss) instanly die which spawns 2 more that instantly die which spawn 4 more that instantly die etc in the end my pc almost offed itself trying to load 187 slime bosses had to quit at floor 157.
BTW I did actually shoot 1 bullet plus ive played atleast 4000 runs and only found synchronizer once. Fun game though.