Nitpick: When the Regents "regent up", the animation shows green circles around them indicating that they had "glamoured" themselves rather than using the usual lightning to transform.
Goof: As soon as Cassidy escapes from the Heart of Meridian, she wears her mortuary dress from "M is for Mercy", whereas a moment later she's still seen in her Guardian outfit.
Elias Van Dahl (from Framed) makes a brief cameo in the battle scene towards the end of the episode.
Joan Lin appears in this episode even though she has no dialogue.
Goof: Just after Will makes her "buster" remark to Phobos and attacks, her skirt turns pink instead of blue.
When Irma says "time out", she actually does a "technical foul" signal of basketball.
Taranee's outfit in this episode seems to be a red and green version of what she was wearing in The Labyrinth.
Look hard: When Blunk plunders Cornelia's drawer, there are some undies dropping right before the faces of Lilian and Christopher.
Goof: When the shot zooms out after Will declines Hay Lin's ice cream offer, we can see Taranee sitting next to Cornelia. Then, when Will is explaining how she couldn't hold on to Nerissa's seal, Taranee's gone, and Irma is sitting beside Cornelia. Finally, when the shot comes back to the entire group after the lights come on, Taranee's back, once again sitting next to Cornelia.
Goof: In the classroom right before Phobos causes Taranee to blow up her experiment, Cornelia (at a table in front of the former) and Will (at a table in the very back left-hand side of the room) can be seen whereas we know from previous episodes that Will and Cornelia are a grade higher that the other three Guardians and should not be in the same science class.
Look hard: In the hall outside the classroom blown up by Taranee during the science project, Sailor Moon in her school outfit makes another appearance.
Goof: When the girls are talking to Napoleon, Matt is dressed up as a jester. One could assume that happened because Lilian wished him as so. But then why is he back in his regular clothes later on?
Goof: Cassidy and altermere Yan Lin combine their powers to freeze Irma and Hay Lin to the wall. When the freezing occurs, Cassidy is temporarily absent, then she reappears as though she didn't move.
Goof: When the dragon unleashes his fire before Irma and Hay Lin fend him off, Taranee's glasses are missing.
Goof: After Nerissa uses her powers to dump the tray of food all over the Guardians (and Matt), we can see that Andrew has Matt's hair - color and all - when the shot comes back to Nerissa.
Goof: While Nerissa's mojo supposedly enthrals every male around her, a young man is yet seen walking past her, impervious to her charm, during the mall's grand opening (after W.I.T.C.H. agrees to battle C.H.Y.K.N.).
Look hard: When Hay Lin takes the screen and Nerissa stands behind her, her wings are completely colourless.
Goof: When the girls flee away from C.H.Y.K.N. to Kandrakhar, the exterior is intact while the interior is still in ruins.
Goof: It is clearly shown that Cassidy's gloves are teal. However when she is seen from the back, deglamouring or shooting water at Irma, her gloves are pink.
Goof: When Cassidy, Halinor, Yan Lin and Kadma deglamour in the mall, their tops remain unchanged. Yet when the camera shifts to W.I.T.C.H. and resume on C.H.Y.K, they are now wearing their Guardian tops.