Shortly after the evolution of Dos cells into a multicellular eukaryotic (containing a nucleus), three forms of heterotrophic (get their energy from eating other organisms) organisms evolved in these waters. Today, scientists identify them as the precursor of water animals that are dangerously decreasing in the populated shores of Rhoneah continent. There is a current effort to clone these precious water animals and introduce them in water animal depleted regions of South Euseus and Capripous oceans. Scientists are studying the following three ancient aquatic animals:

Mud Flats animals are often found buried in the mud. The "mudflat metropolis" is composed of burrowers and tube dwellers that help oxygen-rich seawater percolate to keep the mud alive. The main food pathway in the mudflat is through the bacterial breakdown and decay of plant material such as rumples, mudflat grass, and psilos. There are also tiny fish-like animals that inhabit this area. They are like fish because they are symmetrical and they swim using some crude fins but they are not like fish because they don't have bone endoskeletons. These swimming animals of the mud flats are filter feeders. Mudflats are found on the western shores of Mandalea where the cold up swelling of waters creates a large expanse of muddy banks perfect for hardy mud flat animals.

Open Ocean animals are strong swimmers and make up over 20,000 diverse species of fish. Most open ocean animals tend to be streamlined, have countershading (light underneath the body and dark on the back) and gain protection from predators by swimming together in large schools. These animals have endoskeletons made of bone. Expect to see these animals throughout Euseus and Capripous oceans.

Shallow Rocky Shore animals have a unique mechanism to withstand strong waves that constantly buffet their environment. Smaller animals have hard shells and filamentous anchors that root them firmly on the rocks. Some animals found in this environment have hundreds of tube feet to propel them along the rocks while fighting not to get tossed by the strong currents. Bigger animals start as tiny polyps that float under the waters and soon land next to their parent and like a plant seed, anchor itself there and start to mature developing long tentacles to capture or filter their food. Shallow rocky shores are found sloping down between the boundaries connecting Penancea, Rhoneah, and Mandalea