The Isugen are a race of bipedal vaguely-humanoid cetaceans, vaguely resembling various species of dolphins and small whales, such as orcas.
The race evolved in the underwater caverns deep in the murky waters off-shore of the location of their major land-based city, and feature poor eyesight, but enhanced hearing and echolocation abilities as a result. Isugen are augmented at a young age, so they can handle life on dry land when visiting other areas.
They are typically colored in various shades of gray, with no hair, but feature claws on their webbed hands and digitigrade feet. they are typically slim yet well built and have a thin layer of blubber between their muscles and thick rubbery skin, though obesity is uncommon as it tends to slow one down in liquid and on land, it is not impossible.
While the Isugen do have a standing military with very effective tactics and weapons, their main focus is science and exploration.
Isugen culture places heavy emphasis on individuality, freedom, and choice. Although they do place some limitations on what people can do, since every civilization needs laws for the sake of stability.
They're generally a peaceful people that try to avoid taking sides in conflict, and don't enjoy engaging in war. But they will stand up for their values and anyone they see as an ally.