This article contains information on a subject that is not considered canon in Steven Universe.
When KO finds himself trapped inside a mysterious place, he encounters other Cartoon Network heroes and they band together to escape.
In a destroyed city, Strike attacks two shadowed heroes. Fed up by their hiding, he summons K.O. to fight instead. Just as he is about to destroy him, one of the shadowed heroes saves him. Garnet reveals herself to be this shadow. The other shadowed hero is Ben 10, and they run. Strike sends his blaster after them, and after some brief introductions, the blaster engages them. Ben turns into Four Arms and pushes it back. The blaster retaliates by blasting off his Omnitrix, preventing him from turning back. Garnet also loses her glasses, which enabled her to focus her future vision. The three escape and manage to temporarily bring down the blaster.
Escaping into an abandoned building, they find numerous other heroes frozen in stone with red X's on them. They do find one hero named Raven, who managed to survive Strike's attack due to a protection spell. She explains that the city they are in used to be a bustling utopia for all sorts of heroes until Strike showed up to destroy all of them and steal their powers. He then began summoning heroes to destroy from other dimensions. Raven has also lost most of her powers, only able to levitate. The four decide to attack Strike's lair head on, even forming their team name: O.K. Ben Let's Go Universe.
Using Raven's levitation and Garnet and K.O's punches, the quartet evades traps and monsters sent by Strike and make it to his lair. The blaster shows up once more and corners them. Strike arrives and begins powering up. K.O. uses this opportunity to grab the blaster, figuring that its appearance as a pen would indicate it could create as well as destroy. K.O. restores his new friend's powers and they engage Strike. He sends X energy blasts which Garnet deflects with her rapid-fire gauntlet strikes and future vision while Raven uses a blast of dark energy.
When Ben tries to change, he only changes into the various heroes he saw before. K.O. explains that when he used the pen to restore the Omnitrix, the powers that Strike has stolen came with it. K.O. then uses a power fist to launch Ben at the stunned Strike. Ben then transforms into many heroes as he delivers a devastating final hit, destroying Strike. Garnet reprograms the blaster, and the city, as well as all the heroes, are restored by it. Raven opens portals to their home dimensions, and she and Ben both depart. Before Garnet leaves, she uses the blaster to create a POW card of herself for K.O. and leaves for her dimension. K.O. returns to his home and wakes up in Gar's Bodega. Initially believing he was dreaming, he then discovers the Garnet POW card, realizing that recent events were true.
- Ben Tennyson
- Steven Universe (cameo)
- Pearl (cameo)
- Amethyst (cameo)
- Robin (shadow cameo)
- Starfire (shadow cameo)
- Cyborg (shadow cameo)
- Beast Boy (shadow cameo; mentioned)
- Weasel (stone cameo)
- Yumi (stone cameo)
- Chowder (stone cameo; Ben's transformation)
- Schnitzel (stone cameo)
- Edd (Double D) (stone cameo; Ben's transformation)
- Moxy (stone cameo; Ben's transformation)
- Finn the Human (Ben's transformation)
- Jake the Dog (watch cameo; stone cameo, Ben's transformation)
- Mordecai (Ben's transformation)
- Hi Five Ghost (stone cameo)
- Buttercup (Ben's transformation)
- Talking Dog (stone cameo)
- Prohyas Warrior (watch cameo, stone cameo; Ben's transformation)
- Gumball (stone cameo; Ben's transformation)
- Festro (stone cameo; Ben's transformation)
- Uncle Grandpa (Ben's transformation)
- Robot Jones (stone cameo; Ben's transformation)
- Kelsey (stone cameo)
- Mortimer (stone cameo)
- Ilana (stone cameo)
- Octus (stone cameo)
- Frankie (stone cameo)
- Juniper Lee (stone cameo)
- Black Hat (stone cameo)
- Golly Gopher (stone cameo)
- Larry 3000 (stone cameo)
- Lu (stone cameo)
- Wirt (stone cameo, Ben's transformation)
- Gregory (stone cameo)
- Jason Funderburker (stone cameo)
- Sheep (stone cameo)
- Captain K'nuckles (stone cameo, Ben's Transformation)
- Grim (stone cameo, Ben's Transformation)
- Courage (stone cameo)
- Supercow (Ben's transformation)
- Chicken (stone cameo)
- Grizzly (stone cameo, Ben's transformation)
- Dexter (Ben's transformation)
- Monkey (stone cameo; Ben's transformation)
- Jeff (stone cameo; Ben's transformation)
- Jorel's Brother (stone cameo)
- Johnny Bravo (Ben's transformation)
- Carl (stone cameo)
- Lazlo (stone cameo)
- Jake Spidermonkey (stone cameo)
- Numbuh 5 (stone cameo)
- Erin (stone cameo)
- Kiva Andru (stone cameo)
- Duncan Rosenblatt (stone cameo)
- One-One (stone cameo)
- Tiggy (stone cameo)
- Generator Rex (stone cameo)
- Major Dr. Ghastly (stone cameo)
- Apple (stone cameo)
- Rodney J. Squirrel (stone cameo)
- Hedgehog (stone cameo)
- King Rufus (stone cameo)
- Valentino (stone cameo)
- Blastus (stone cameo)
- Alfe (stone cameo)
- Periwinkle (stone cameo)
- Two characters from The Fancies (stone cameo)
- Toonix (cameo)
- Clyde 49 (cameo)
- Super Chunk Kid (cameo)
- Ian Jones-Quartey stated that he was inspired by Cartoon Network's earlier crossover episodes, such as those that aired in the late 1990's and early 2000's, in the production of Crossover Nexus.
- OK K.O.! Let's Be Heroes storyboarder, Parker Simmons, stated that this would be his last contribution as a storyboarder.
- Even though the events of this episode are not canon to Steven Universe, Ian Jones-Quartey stated that one canon thing about Garnet is revealed in it. This is the function of Garnet's visor.
- Garnet lacks her wedding rings during the crossover. This seems to suggest she's meant to come from a point in time prior to the events of "Reunited" and the "Heart of the Crystal Gems" arc as a whole.
- The image used in Garnet's Pow Card is the same image that was edited together specifically for Garnet's page in this wiki.
- In the cameo of the other Crystal Gems, Amethyst and Pearl have their upgraded whip and spear from "Bismuth", despite Amethyst being in her previous regeneration, which was before she met Bismuth.
- In this same shot, Pearl's star is a deep blue, and her socks are missing.
- When Garnet and KO punch the piranha, Garnet has a complete glove instead of just covering her middle finger.
View the episode's transcript here.