10 Best Supervillains Who Only Appear Once

Being a spoilt rich boy, Peter Dudley spent his whole life getting what he wanted. So, when he saw Mera swimming with Aquaman, he assumed he could win over the Atlantean superheroine with ease. When Dudley learned Mera wasn't interested in him despite his wealth, he assumed she would change her mind if he obtained aquatic powers.

After hiring a scientist to endow him with abilities akin to Aquaman, Dudley assumed he would become irresistible to Mera. The experiment gave Dudley all of the marine monarch's powers but also turned him into a misshapen deranged brute called Aquabeast.

When Dudley located Mera and attempted to kidnap her, Aquaman stepped in to challenge his devious doppelgänger. Sadly, Aquabeast's strength far exceeded that of the Atlantean king, allowing him to vanquish Aquaman with little effort. Emerging victorious Aquabeast seized Mera and fled.

However, he suddenly bumped into an alien called Hammuri, who then sucked Aquabeast into a whirlpool, seemingly killing him. Even though Aquabeast's undoing was anticlimactic and completely out of nowhere, he deserves a bit more credit since he was the first supervillain to utterly dominate Aquaman.