At the end of the last scene after the Wonder Twins return from Exxor, Aquaman's right glove is missing.
When Orville tells Lex to smile when he's about to change his image, Luthor tells him to shut up. Notice the collar of his outer shirt turns green then back to lavender.
In one shot during Superman's battle with Lex Luthor, his "S" chest logo is backward. After the sun creatures contributed to his defeat, the logo is inverted with a yellow "S" inside a red shield instead of the traditional red "S" inside the yellow shield.
When Superman uses his chill breath to extinguish the fire engulfing the village, he's able to do so despite the fact there are flames behind him. Note that he accomplished this without turning around.
(Last scene after the Wonder Twins return from vacation)
Zan: Anything exciting happen while we were gone?
Aquaman: Nothing special, Zan.
Superman: Just a nice, sunny weekend.
The Others: Riiiiiiiiiight!!!
Luthor: They've (the sun creatures) destroyed my hovercraft!
Orville: And we're surrounded by fire! We wouldn't be in this mess if it weren't for those no good SuperFriends!
Luthor: Of course...the SuperFriends! You're a genius, you idiot! With this radio control switch, I'll free the SuperFriends. Let them destroy those cursed sun creatures! (Presses a green button to set his plan in motion)
The Wonder Twins and Gleek only appear briefly in this episode.
Inspiration from Earlier Episodes
This episode borrows quite a bit from Challenge of the SuperFriends. The idea of having Lex Luthor make a deal with fiery beings from another world came from The Fearians, in which Captain Cold bargains with the titular alien race from Venus. Later on in the episode, Lex Luthor uses elaborate disguises to lure the SuperFriends to the same spot in order to trap them, just like The Swamp of the Living Dead. Finally, like in Swamp of the Living Dead, Luthor is betrayed by his newfound allies and frees the doomed SuperFriends so that they can sort out the fine mess that he created.
Strangely enough, this is the only episode of any SuperFriends series in which Jimmy Olsen is seen. But of course, he was being impersonated by Orville.
Stanley Jones returns as the voice of Lex Luthor in this episode. Mr. Jones supplied the voice of Lex during the entire run of Challenge of the SuperFriends.