The American theme of Diana's costume was explained by Pérez in the Challenge of the Gods storyline in which Diana engaged in a series of trials arranged by Zeus as punishment for refusing his advances. Diana met the spirit of Steve Trevor's mother, Diana Trevor, who was clad in armor identical to her own. Trevor revealed that during World War II she had crashed on Themyscira while on duty as a U.S. Army pilot. She blundered into an Amazon battle against Cottus, a multi-armed demon, at the portal to the underworld. Trevor was drawn into the battle, although she was armed only with her side arm. She wounded the beast before suffering a mortal blow, allowing the Amazons to reseal the portal.
During a training session observed by Hippolyta, Diana sparred against her fellow warriors, demonstrating her weapons expertise and defeating each of them swiftly. Her final opponent was Antiope herself. The two fought with all their might. Diana managed to disarm Antiope and looked toward her mother for approval. Antiope seized the opportunity to push Diana to the ground and pick up her sword, admonishing her for letting her her guard down. As Antiope slashed at her and forced her backwards, Diana instinctively brought her arms together to block the attack. She clashed her arm gauntlets together, resulting in her unleashing a powerful shock-wave that sent Antiope flying back and left all spectating Amazons there, including Diana herself, in complete shock.
The chief chemist associated with General Ludendorff who specializes in chemistry and poisons. On her role, Anaya said, "Well, it was a small role in this big ensemble, but it is an important character in the story. I'm going to be a big nightmare" for Wonder Woman and Steve Trevor. Describing her character, Anaya said, "Dr. Maru loves rage and enjoys people's pain. She's creating terrible weapons, and her purpose in life is to kill as many people as possible, and provoke as much pain as possible". She researched World War I and Fritz Haber, the scientist who created mustard gas, to prepare for the role. On the character's facial scars, Anaya stated, "I went to Patty Jenkins and asked, 'What happened to her?' And she said, 'She did it on purpose.' I was like, 'What? Patty, you're going further than I ever imagined.' She said, 'She wants to provoke painful suffering, so she tested her own gas on her own face. She wanted to know how deep this form of her gas would go, so she put it on her own face.' You can see half of her face is completely gone. This is the sadistic side of Dr. Maru". She also stated her character "is quite the opposite to the lead role of this movie, one of the strongest characters ever of DC comics, Wonder Woman. I can tell you that Doctor Poison is someone with a capacity to provoke so much pain." On Dr. Maru's relationship with General Ludendorff, Anaya said, "I think that they have a relationship based on loyalty. Ludendorff is a very tormented General that lacks self-confidence. That's why, in part, he takes these drugs that Dr. Poison gives him. They are from different worlds, but they complement each other".
The Diana Prince alias also played an important role after the events of Infinite Crisis. Wonder Woman was broadcast worldwide killing a villain named Maxwell Lord, as he was mind controlling Superman into killing Batman. When Wonder Woman caught him in her lasso, demanding to know how to stop Superman, Maxwell revealed that the only way to stop him was to kill Lord, so as a last resort Diana snapped his neck. To recover from the trauma of killing another person, the Amazon went into a self-imposed exile for one year. On her return to public life, Diana realized that her life as a full-time celebrity superhero and ambassador had kept her removed from humanity. Because of this she assumed the persona of Diana Prince and became an agent at the Department of Metahuman Affairs. During a later battle with the witch Circe, a spell was placed on Diana leaving her powerless when not in the guise of Wonder Woman.