Continuity mistake: When Cyborg first comes into the H.I.V.E. eating hall, we can see several students sitting dispersed among the tables, among them See-More (the guy with the cyclopian helmet) and Kyd Wykkyd (the Batman-type kid). At first the two of them sit at separate tables; but when Cyborg sits down and Jinx, Gizmo and Mammoth confront him, we can see the two sitting shoulder by shoulder at the same table.
Other mistake: Cyborg/Stone attacks his own robot duplicate starting from near his fellow Titans, with his back turned to them. But after he has finished smashing it to pieces (thereby ruining his disguise), he suddenly is positioned so that he actually faces them, without having made any turn-arounds, since he charged his duplicate head-on.