Fall of Atlantis
The bodies of the Trench have uniquely evolved to function at over 2500 meters below sea level, a depth at which the water pressure hurts even the extremely durable Atlanteans. They've adapted to this environment by no longer relying on sight, and are almost entirely nocturnal. They have a fear of light and they usually shy from it. However, they can survive in air without equipment, unlike most Atlanteans.
They are largely savage animals that attack anything that comes near them. However, Aquaman as the true heir of the throne and wielding the Trident of Atlantis, is able to control them, a feat previously thought impossible.