Smoooo
(They do not really have genders, though they do appear male in stature and he is named Excalibur due to reasons that might or might not be explained later in the story, it´s part of the naming sheme of the Iridestin.)
Tson
...as they stepped towards the opening the glow grew stronger until they eventually saw a large orb down in the cavity, which was at the same time shimmering like mercury and glowing from the inside, occassionaly dark blue lightnings ran through the surface and occassionally one lashed out at one of the stalactites, which then likewise lighted up in the same colors, followed by low waves running over the surface in a small radius around the lightnings origin, the entire thing must have a few hundred km´s in diameter, though it difficult to tell as they did not know how far they were away from it...
...Excalibur simply stood there for a while, letting them take in the view...