Ocean Master (DCEU)'s History
Born to King Orvax Marius and Queen Atlanna of Atlantis, Orm became a great warrior under the guidance of chief counselor Nuidis Vulko. At the same time, he developed a strong hatred for the surface after witnessing the damage they were inflicting on the oceans, which is poisoning the Atlantean children.
At some point during his childhood, Orvax discovered that Atlanna sired a half-human son prior to their marriage and banished her to the Trench.After taking his father's place on the throne, Orm began devising a master plan that would both unite the seven kingdoms and destroy the surface in one fell swoop.In order to carry out his plan and become "Ocean Master", he must obtain the support of at least four kingdoms. He also employed the mercenary David Kane and granted him with an advanced suit of armor out of manipulation into killing Arthur as part of Kane's revenge for the death of his father. Orm advances his plan into further stages when he is using the seemingly unprovoked attack as a pretext to declare war on the surface.The more stages he does about his plan of the surface, the more kingdoms are uniting with him such as The Fishermen people. Nereus, the mighty king of Xebel, is showing full support toward Orm, and is ready to join forces with him despite the anger of his daughter, Mera, who has been betrothed to Orm, refuses to aide them and journeys to the surface to ask Arthur for help, earning his trust by saving his father Thomas from a tidal wave sent by Orm himself.Orm would send his men to ambush Arthur which they would capture him. Orm would arrive to visit Arthur who was chained up and announces that Atlanna was executed for the crime of having a half-breed son, blaming Arthur and the surface for her death.He offers Arthur an opportunity to leave forever, but Arthur instead challenges him to a duel in a ring of underwater lava. Orm gains the upper hand and nearly kills Arthur before Mera rescues him. Together, Arthur and Mera journey to the Sahara desert, where the trident was forged, and unlock a holographic message that leads them to Sicily, where they retrieve the trident’s coordinates.
Meanwhile, Orm provides David with Atlantean armor and weaponry and sends him to stop them, imprisons Vulko upon learning of his betrayal, and coerces the remaining five kingdoms of Atlantis to pledge allegiance to him and his campaign against the surface, knowing that if he obtains support from at least four kingdoms, he will be titled "Ocean Master" and be granted with unstoppable power.To prepare for the upcoming battle of the surface world, he tries to force the Kingdom of the Brine to join him by defeating them at war. However, the battle was interrupted by Aquaman, Mera, the Trench and Karathen.
Upon learning that his brother Arthur has already got hold of the trident and became the Aquaman, Orm gives the green light for the war to begin and the surface world begins to suffer from massive attacks of Atlantis. Arthur, Mera, and Atlanna lead an army of marine creatures in a lengthy and destructive battle against Orm and his followers, who renounce their obedience to Orm and embrace Arthur as the true king upon learning he wields the trident.Arthur and Orm are arriving to the surface world with a submarine, and entering into brutal duel. Arthur defeats Orm in combat but chooses to spare his life, and Orm accepts his fate after discovering Arthur has found and rescued their mother