The Justice League may be saving the Earth on the big screen, but they’re championing another cause in real life.

Ben Affleck, Ray Fisher, Gal Gadot, Jason Momoa and Ezra Miller took a break from the DC superhero set to film an endorsement for Rezpect Our Water campaign on Change.org, an online petition to stop the construction of Dakota Access Pipeline.

The petition was started by the youth members of the Standing Rock Sioux Tribe who reside near the Missouri River. According to the petition, a private oil company wants to build a pipeline that would cross the Missouri River less than a mile away from the Standing Rock Reservation.

The tribe is worried about the environmental fallout from the construction of the pipeline and potential leaks.

“As a gang of earth defenders, we want to send a big shout out to the Oceti Sakowin and those who stand with them in opposing the Dakota Access Pipeline,” Miller said. The Oceti Sakowin is the proper name for the Sioux.

While Affleck (Batman), Fisher (Cyborg), Gadot (Wonder Woman) and Miller (The Flash) were all out of costume, a shirtless Momoa appeared to be wearing his Aquaman shorts.

“Justice League” opens in theaters on November 10, 2017.