The following robots were destroyed by Zeus.
AXELROD His head was almost knocked off. After that, he was punched in half.Based off of what I saw in the movie, he had a system crash, which allowed his fists to move after being completely broken.
BLAC JAC During his fight with Zeus, his facemask was punched off.Then Zeus landed a final punch to the back of the head.
GRIDLOCK Gridlock was the first bot to land a punch on Zeus (which makes Atom the second one to land a punch on him). He caught a nukefist to the head, which was crushed, thus destroying Gridlock.
DANGER ZONE Danger zone was by far the worst death ive ever seen. His core was ripped outh during the 1st round and that sure killed him.