Factual error: When the 747-aircraft of the fake German airline is being shown, you can see the German flag on the plane. But you also see an "N-xxxxx" registration which stands for USA. If it were a real German plane, it would have a "D-xxxx" registration.
Triumvirate of Terror! - S3-E8
Factual error: During the final fight in Lex's lair, Joker gives Batman a good smack with his large hammer. As is common in this show, when a good hit is delivered, a freeze frame is show with the figures moving in slow motion with a stylized colorful backdrop to add to the drama dynamics. But as Joker delivers this hit and this stylized shot is shown, the show cuts to some inmates in a prison cell watching the fight on TV. The same stylized shot is shown on their TV, where it would be show like that there, only to us. They would have just seen Joker hit Batman with the hammer and him fly off in real time with no stylized back drop or slow mo. (00:20:00)
Factual error: When the doctors are testing the contagiousness of Andromeda on the rats and monkey, in a highly secure, bio-sealed environment, the robotic arm that does the work simply pushes the containers together - no seals, no suction or vacuum. There would be absolutely no chance whatsoever of a real bio-research lab doing this so casually.
Factual error: When the X-Men are surfacing after crashing their jet into the dam, Shadowcat is shown phasing through the jet and pulling Wolverine and Beast through with her. Since Wolverine's bones are coated with a heavy metal, he wouldn't be able to float to the surface. He would sink instead. (00:14:57)