"Lords of Luck" part 2.
Green Lantern and Supergirl are off to Ventura on the trail of a bizarre case! Ventura is a planet-wide casino, which would be wild enough, but it has also become a backdrop for the Rann-Thanagar War!
As Hal Jordan and Supergirl fly through space, Kara is seemingly flirting with him. He keeps reminding himself, she's only seventeen. They are searching for the Book of Destiny that has been stolen. They arrive on the planet Ventura (which is basically one giant casino) as Batman follows a lead on Earth. It seems the planet has strict security measures and also don't like Green Lanterns' presence. Hal has to go undercover and wants Supergirl as backup.
On Earth, Batman and Blue Beetle are tracking down an alien assassin.
The thief will not have much time to use the Book before he is detected by security on Ventura. Supergirl continues with her flirting until Hal has to finally put his foot down. Supergirl appears hurt and takes off. Suddenly in the combat arena, she appears dressed as a little girl and is the challenger in the next fight. As Supergirl fights a huge creature with no problem, Hal checks out the wager data on that match. There is only one gambler betting on Supergirl because he "knows" the outcome. By the time Hal gets there, the gambler is already gone. Trying to make a get-away, he checks the book and sees himself get struck from behind. Another gambler liberates the book from him after he overheard Hal and Supergirl discussing it. It turns out this alien is in the Rannian Rebel Underground trying to get funds for the Rann-Thanagar War. He prepares to zeta-beam out of there so Hal and Supergirl have to take their fight to Rann. As Hal is "holding" the rebel, they beam out of there before Supergirl can grab hold of him. She is left there with no idea how to get to Rann or Earth. All the betters in the arena see her "S" logo and yell that she was a ringer in the fight. Things do not look too good for her.