WARNING: The following article contains spoilers for Guardians of the Galaxy #3 by Donny Cates, Geoff Shaw, Marte Gracia and VC's Cory Petit, on sale now.
When Marvel relaunched Guardians of the Galaxy in January, it introduced a revamped lineup with new and familiar faces. Joining holdovers Star-Lord and Groot were Beta Ray Bill, Cosmic Ghost Rider, Moondragon and Phyla-Vell. The new Guardians came together when it was revealed that Thanos had found a way to resurrect himself in someone else's body following his death at the hands of Gamora in Infinity Wars.
With the thought of Thanos version 2.0 looming somewhere out in the galaxy, Starfox assembled all of Marvel's cosmic characters together with the idea of killing Gamora, who is the most likely suspect for the Mad Titan to choose as his vessel. When the Black Order attacked the reading of Thanos' will, the villains opened a black hole to kill the heroes while they stole Thanos' corpse.
Cosmic Ghost Rider, Beta Ray Bill, Moondragon and Phyla-Vell escaped to warn Star-Lord and Groot of what took place, but they weren't the only survivors. Starfox, Guardian of the Shi'ar Empire, Nebula and Wraith teamed up to become the Dark Guardians, with Cosmic Ghost Rider ditching the heroic Guardians to join their ranks. Now, a manhunt is underway for Gamora, who has gone underground following her heel turn in Infinity Wars. Of course, you'd think Star-Lord would be all for warning Gamora before the Dark Guardians learn of her whereabouts, but that isn't the case. Thankfully, there is a character willing to do whatever it takes to help his former teammate, even if it means commandeering leadership of the Guardians of the Galaxy from Star-Lord.
All Hail Captain Groot
Infinity Wars saw Gamora go on quite a kill spree -- going by the moniker Requiem, Gamora killed Thanos and Star-Lord, two men who were quite close to her. The use of the Time Stone to rewind time is the only reason Star-Lord is still alive, but that hasn't taken away his memory of being betrayed by Gamora. Guardians of the Galaxy #1-2 have shown Peter Quill mentally struggling to get over being killed and brought back to life, which has left him numb to all the chaos currently ongoing in the galaxy.
When Groot and the rest of the Guardians decide to go help Gamora, Star-Lord refuses to get involved, leaving Groot with no choice but to relieve Peter of his command over the Guardians of the Galaxy, thereby becoming the team's new leader.
We also find out Groot has named Beta Ray Bill as his second officer, meaning Groot doesn't believe Star-Lord is even fit enough to be his second-in-command. Groot takes control of the Ryder, leaving Star-Lord no choice but to tag along, whether he likes it or not.
Before the issue concludes, Peter reveals Gamora is on Halfworld in search of Rocket, which could bring another former Guardian back into the series.
Groot entered Infinity Wars in his Baby Groot form, but left it transformed with the ability to speak in complete sentences -- though he still refers to himself in the third person. This transition makes his new position as the Guardians' Captain even more entertaining, because we know exactly what he's saying. No more guessing games -- Groot is now in charge.