- "Because I don't like you coming here, digging into my business, getting into my life. I wanna be left alone."
"That why you do this? Help these people out here in the middle of nowhere? I read the stories, your good deeds. You think no one sees? You'll join us."
"Strong man is strongest alone. You ever heard that?"
"You ever hear of Superman? He died fighting next to me."
"My point exactly."
"Believe me, we're stronger together. We owe it to him."
"I don't owe anyone anything. Dressed like a bat... You're out of your mind, Bruce Wayne!""
- ―Batman and Aquaman[src]
After he declined Batman's offer and leaving Iceland, Arthur rescued a sailor caught in a storm, taking him to a bar where he deposited him on a table and ordered himself a drink. Realizing that there was something wrong happening, Arthur decided to enter in Atlantean territory.
- "You dare speak of Queen Atlanna that way?"
"Your 'queen' left me on my father's doorstep and never gave me another thought."
"Your mother left you to save your life! You cannot imagine how it hurt her, what it cost her. But you're not a defenseless child now. It would have been her responsibility to follow that monster to the surface and stop it. Now, it's yours."
"Then I'm gonna need something from you."
- ―Mera and Aquaman[src]
After the Attack on the Penetralium, Steppenwolf attacked the Atlantean Stronghold somewhere outside of the legendary and ancient city of Atlantis to retrieve the second Mother Box. The result ended up being nearly the same as in his previous attack. He ultimately managed to retrieve the penultimate Mother Box from the Atlanteans despite their efforts and the help Aquaman, who had to be saved by Princess Mera.
- "Steppenwolf. Tell me what you've learned."
"Two boxes, found and awake! With the combined power of the Motherboxes, I've been able to finish the stronghold's defenses."
- ―DeSaad and Steppenwolf[src]
Mera then spoke with Arthur, who had grown estranged from the Atlantean half of his dual heritage, revealing to him that he hadn't been abandoned by his mother like he'd believed and that her love for him should be what inspires him to protect his people. Pressing further, Mera stated that retrieving the Mother Box is what his mother would have done.