When Venom joined the Guardians of the Galaxy, a skirmish allowed the symbiote to bond with Rocket Racoon and give him the only superpowers he could ever truly desire. After Flash Thompson joined the Guardians of the Galaxy, his symbiote began to display erratic behaviour that eventually became dangerous to his new team. Although the Guardians separated them, Venom escaped his captivity, jumping from host to host which included Rocket. Together, its shape-changing abilities allowed the sarcastic alien to have all the firepower and ammunition he could ever want, even if he isn't completely in control of his actions.
After Iron Man personally vouched for Flash, the solider-turned-symbiote hero left the Secret Avengers to join Peter Quill and his teammates in the Guardians of the Galaxy. While experiencing other worlds and cultures outside of Earth, Flash realized there was still much he did not know about his symbiote which not only allowed him to walk but also become a hero similar to his idol, Spider-Man. On more than one occasion, the symbiote or "klyntar" ignored Flash's requests and became difficult to control. After an incident where Venom attacked the Guardians, they were able to incapacitate it thanks to technology provided to them by Tony Stark in case of such an emergency. While Flash appeared to sleep off the separation, the symbiote escaped captivity to bond with Rocket's close friend Groot, resuming its earlier attack.
In Guardians of the Galaxy # 22 by Brian Michael Bendis, Valerio Schiti and David Lopez, the Guardians attempt to subdue the new Venom while not hurting their friend or damaging their ship beyond repair. When the symbiote eventually releases Groot, it makes a pass for Rocket and when that is unsuccessful, it flees into the inner workings of the ship. While Star-Lord and Gamora debate about what to do with Flash, the search for Venom ends when it gets the drop on Rocket again. Although Rocket resists as the black and white ooze bonds with him, Groot and Drax soon face a new Venom who orders the Guardians to leave the ship or else, backing his ultimatum with a pair of multi-barreled guns formed from Venom's essence.
Although Rocket Racoon has evolved over the years, one thing has remained constant and that is his love of guns. Regardless of its size or capability, Rocket will wield any weapon he can get his hands on, his adorable animated-like appearance juxtaposed with his enjoyment in violence and chaos. His MCU counterpart voiced by Bradley Cooper embraced this character trait, maniacally laughing while blasting away countless rounds at any enemy unlucky to be caught in his peripheral during battle. The Venom symbiote is known to model itself after its host's desires and enhance their current abilities and with Rocket, it gave him unlimited firepower courtesy of dual Gatling gun-like arms. Although the Guardians appear to be less in control when under Venom's influence, the symbiote only made Rocket even more dangerous, willing to attack his teammates including his close friend Groot.
Although the Venomized Rocket appeared willing to attack the others, it was unwilling to attack Peter Quill, requesting that Star-Lord and the other Guardians allow him to take the ship for his own mission. When Peter's appeal to Venom's better judgement failed, the symbiote left Rocket to bond with another, someone even more dangerous than Rocket: Drax the Destroyer. Although his time as Venom was brief, the experience allowed fans to get a brief glimpse of a version of Rocket Racoon that's more formidable than he already is, an entity that the Guardians of the Galaxy know is no laughing matter.