WARNING: The following contains spoilers for "Ladies' Night Out" by Paula Sevenbergen, John Kalisz, Becca Carey, Emanuela Lupacchino, and Wade von Grawbadger in Future State: The Next Batman #4, on sale now.
By most standards, Superman's dog, Krypto, is arguably the most famous pet in the DC Universe. The beloved dog has been in so many comics, not just as Clark Kent's beloved sidekick on the Kent farm, but as an ally for Superboy/Conner Kent and the entire Superman family. And over the years, Krypto has notably evolved into Supergirl's best friend, especially in the Future State continuity where the two were buried on the moon alongside each other.
However, in The Next Batman #4, the Gotham City Sirens back-up reveals Krypto's isn't the only super-pet in Future State, since Poison ivy has her own intimidating pet, a monstrous venus fly trap named Rover.
Ivy and Catwoman have stolen the sentient android, Dee Dee, from Dax Dilton, a tycoon who has worked with the Magistrate to develop Cybers to hunt down masks. Dee's promised them data that could give the Resistance clues on how to bring the Cybers down, but after promising her a night out on the town, things go awry. They end up fleeing Sam Bradley's bar after a shootout with the Peacekeeper's forces and head to a cozy cottage Ivy has as a hideout.
As Catwoman nurses her wounds, she's woken up by a cute plant dog. Ivy's created a sentient plant pooch out of leaves and flowers, and while it seems lovable and playful, there's a darkness underneath. That vicious darkness is unleashed when cops ambush the ladies in the spring while they were relaxing. Fully armed, their mission is to kill Ivy and the Cat and capture Dee as Dax wants her mind back due to the sensitive intel it contains.
But before the cops can enact their disgusting brand of justice, we see Rover's full form. The 'dog' is basically a living, breathing Venus flytrap that starts devouring the police left. They're humans, not Cybers, so they're easy to digest which allows the ladies time to make a getaway. But as they depart, Ivy blows up the barn and seemingly leaves Rover to either roam the bushy wilderness or die.
Wthis seems cruel, Ivy can regenerate Rover wherever she goes once there's flora and fauna. The ladies are afraid of the animal, though, because after seeing its rabid form, Ivy admits it loves eating humans and animals, which means that it's not something she can bring to life any and everywhere.
Despite Dee sacrificing her life when they meet Dax's legion up on the road, Ivy and Catwoman escape and slip the data to the Resistance. Ivy even opens up a bar to honor Dee weeks later, fondly remembering the time they all spent on the run and their fun times with Rover who more than served its purpose and protected them, helping them strengthen the rebels' cause.