Continuity mistake: When Nuclear Man arrives on Earth, he enters a shady place which makes him loose his power and cools his body, producing some frozen-like smoke. The next two times that he enters a dark place (inside the elevator and in space) he doesn't produce the smoke. FX budget problems here?
New this month Revealing mistake: During the Metropolis destruction scene, Nuclear Man sends a SWAT truck spinning around. When he lifts it up with his rays coming from his hands, you can see the truck is being lifted up by a visible white wire.
Revealing mistake: When Superman saves the people that Nuclear Man throws up into the air, as they lower you can see the support wires holding them up.