Now it just so happens that right after you voted for Aquaman on my previous article, the first image of him was tweeted by Zack Snyder! So, without further ado, here they are. (Note, there are only two here instead of my regular four because Aquaman really only has two good bad guys.)
Orm, the half-brother of Aquaman is always wishing to overthrow him. This character could bring a Thor-Loki dynamic to the film.
One of DC's most merciless killers, Manta even went as far as murdering Aquaman's only son in cold blood, and it would mean that the DCCU has more diverse heroes and villains (please don't take that the wrong way).