The Children of Arion is a fictional organization in the DC universe whose first appearance was in 2016 in issue #8 of the 4th volume of the Secret Six comics series.
The Children of Arion are a cult dedicated to the Dark Giants. They claim to be True Atlanteans and recently manipulated the Secret Six a group of super-villains and sometimes heroes to help bring about the return of the Dark Giants. Upon their failure, several of them were consumed by Thrumm, the greatest of the Dark Giants. They appear like normal humans but it's an illusion as they are actually mutated humans that have reptilian or fish like features (e.g. scales).