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Mera's Trident was the royal weapon of Atlantis, and it's symbol, thus the trident only works for Atlantean royalty, shocking anyone else who tries to use its powers. This also makes Arthur resistant to its magic, as he is of royal Atlantean blood. The trident has magical elements to control lightning and water, and is capable to create tidal waves, energy projection and projecting electricity.

Orm uses the trident's magic, which can only be wielded by royalty, to imprison the Justice League. After Arthur wakes up, he is shown to be more resistant to it than the other Justice League members and can use it. It might be justified in that because Arthur is a illegitimate, Orm's egotistical viewpoint does not consider the possibility to believe that meant Arthur couldn't use the trident's magic. Orm calls the trident to his hand at one point. Wonder Woman wasn't strong enough to stop it from reaching him. Orm does this with the trident to slow his fall during the final battle. Arthur learns how to use his trident rather quickly.

During Doomsday's rampage, Arthur and the other League members tried to hold Doomsday back, with Arthur using the trident. Because of it's magical nature, Doomsday was hurt by the Trident, although it did not stop Arthur being knocked out by Doomsday

After the Justice Leagues failed invasion of Apokolips, Aquaman was killed by Darkseid's Omega Beams and Mera was brainwashed, her body fused to Apokoliptic technology, and turned into one of his Furies and became the new wielder of the trident.

Two Years later, when Superman, John Constantine, Robin, Raven, and Etrigan infiltrated Apokolips, they are confronted by the Furies. Along with Hawkman, Mera attacks superman using her hydrokinesis and the trident. After Wonder Woman is freed from her mind control, she fights the Furies by herself to allow the heroes to enter the reactor room, but Mera stabs her left shoulder with her trident; once Cyborg is freed from his programming, the technology of the planet shuts down, freeing the other Furies as well.

On Earth, at the ruins of Titans Tower, despite their victory, the heroes laments on their failures and losses, and Mera cries in mourning of Aquaman, while being comforted by Ace. As Flash runs to reset the timeline, creating another Flashpoint, Mera watches alongside Ace ,while still holding her trident, as they disappear into the unknown.