In the DC Super Hero Girls episode Rage Cat, we are introduced to the show’s version of Dex-Starr (and by extension, the wider Red Lantern Corps within the show’s universe).
While not the first version of Dex-Starr in animated form (in the very least he also appeared in the criminally short-lived Justice League Action), this version was himself a lot of fun. Not least because it introduced an amusing weakness for Wonder Woman (turns out she’s allergic to cats, something Dex-Starr gleefully abuses when he realises what’s up).
Kind of confused why Jessica didn’t take him to Kara to look after, but since the episodes are only 11 minutes I guess they just didn’t have time.
Look at this pissed-off bloodthirsty evil alien cat from beyond the stars