The Atlanteans have proven many times before that they do possess great superhuman abilities and believe they themselves belong on the list of powerful races such as the Kryptonians and Thanagarians. They also have the ability to control the ocean, which is vastly made up of 75% of our world, as well as swim underneath the weight of the ocean floor, thus accumulating great amount of strength and durability as part of their main feats.
The Atlanteans all possess superhuman abilities and are one of the strongest races in DCU. Being of Atlantean Royalty, Aquaman and any blood of the royal family acquire great amount of superhuman strength and abilities, being able to lift 100 tons of weight in the water (25x tons more of ocean depth) as well as on land. Their trained warriors of the Atlantean Army also had the ability to take on the Justice League and their reinforcements and have been shown to be a brutal force in the New 52. Although, their full potential is yet to be determined, they have proven that they deserve to be listed has a powerhouse race.
The Atlanteans were once a thriving, powerful race in the world.
Murk and his frontline army are one of the strongest forces in the Atlantean army, considered this they are brute powerhouses. He has trained in the fire pits, being the only survivor to make it out and has defended King Orm against the Deep Six and Fire Trolls. Their full potential has yet to be determined. However within these next couple issues of Aquaman, we'll probably get to see some feats of theirs (Scans from Aquaman #17).
As for Atlantean artifacts, the full potential has yet to be determined. However, it is known that the relics are in fact very powerful weaponry in future technology and could cause much catastrophe.