Luthor seems to kill the remaining SuperFriends in the following sequence: Robin, then Flash and Aquaman, Samurai and Apache Chief, and lastly Green Lantern, Black Vulcan and Hawkman. But the camera pan of the bodies in reverse order is incorrect as after the last three together, it shows Flash and Aquaman before Samurai and Apache Chief.
Just after Luthor crosses Batman off the poster of the SuperFriends, the next faraway shot of the scene at the Hall of Doom shows the poster completely blank except for the "X."
Trivia: This episode is dated December 1978 according to Batman's tombstone.
When the SuperFriends explained their plan on faking out the Legion of Doom, Apache Chief is seen holding the hazmat suit he used to get rid of the Noxium. But in the last shot, the suit isn't seen at all.
The beam fired from Luthor's fake disintegrator beam is colored red. But when it bounces off Superman, the beam color is yellow.
Just before Superman wraps him up in the Daily Planet's printing press, a significant portion of Solomon Grundy's jacket is colored blue like his shirt.
At Batman's funeral, Robin's glove is missing when he wipes away a tear, but it's on his hand in the next shot.
Trivia: The name of the villain who created the noxium crystal, Dr. Natas, is "Satan" spelled backwards.
Green Lantern uses a baseball bat from his ring to knock away Sinestro's laser beam. GL's ring shouldn't work against anything from Sinestro's because of its weakness to yellow.
When Luthor, Grundy, and Sinestro are disguised as construction workers at the start of the episode, Sinestro's mask is a bright pinkish color almost like his real skin. Nobody seems to notice.
A closeup on Hawkman at the military base has the green portion of his costume missing, leaving his legs bare.
Just moments after Lex Luthor and the Legion of Doom are celebrating their defeat of Wonder Woman at Paradise Island, Luthor and Solomon Grundy are already in Metropolis holding Lois Lane and Perry White hostage at the Daily Planet waiting for Superman to come to the rescue. Unless they used an instantaneous transport device, it would have taken the villians longer to get to Metropolis.
How is it that Wonder Woman (or was it her android double) was capable of instantly teleporting herself to Paradise Island? Diana Prince indeed uses the spinning motion to change into Wonder Woman, but there was never any indication that this could also magically return her home.
If the Superfriends' plan from the beginning was to fake their deaths, why the heck were they so concerned about being killed when they were in their private hideouts. Other then the audience, who were they pretending for when they were the only ones there?
For the first and hopefully final time, the Riddler displays the ability to use an (apparently real) magic wand to pull a giant mutated rabbit out of a top hat (??).
The "Gotham Department of Sanitation" lettering changes on the garbage truck before/after the Riddler goes by it.
Just before the Superfriends leave Earth in exile, you can see Batman among them...despite the fact he is believed dead at this point in the episode.
Before Flash uses his super speed to get himself and Apache Chief free of Sinestro's energy diamond, Scarecrow, viewing the monitor as some of the other SuperFriends are tangling with the giant water hand, is saying "Now to sit back and watch those super fools get crushed out of existence". However, he's speaking with Sinestro's voice.
Sinestro traps Flash and Apache Chief in a giant energy diamond. But before they get free, its shape changes into a hexagon and then back to a diamond.
After they receive Luthor's distress call and before Superman, Black Vulcan, and Green Lantern depart the Hall of Justice to help the Legion, GL's boots are briefly colored white before changing to their regular green.