there were 12 main gods, and they all sat together on a sort of council. however, there were many other minor gods, much the same way we have patron saints. some of them are important, like the patron saint of love; and some aren't, like the patron saint of taxi drivers. :-) the same was true of the greek gods.
The realms of the Greek gods and goddesses vary due to what they are the gods/goddesses of.
On Mt Olympus though some did live in other realms such as Poseidon who lived in the sea greek gods are cool
He is Greek god, but he does have a roman version Jupiter
the greek god hermes the god of messages
There is no Greek god mercury, he was a roman god, and he was the god of war and weapons.
The Greek god of sleep was Hypnos.
On Mt Olympus though some did live in other realms such as Poseidon who lived in the sea greek gods are cool
If you are talking about Greek mythology then the answer is Oceanus. However he wasn't exactly a God rather a Titan - a slight but significant difference.
He is the god of the sea.
The ancient Greek messenger, thief, spy, and god, Hermes, carried the caduceus staff, which was said to be a sign of his ability to move between the realms.
He is Greek god, but he does have a roman version Jupiter
There are three major realms: The sky, the sea, and the underworld. Zeus is the god of the sky, Poseidon is god of the sea, and Hades is god of the underworld. Also, they are all sons of Rhea, a Titan, so all of the other gods and goddesses are their sons or daughters.
There is no Greek god "Sades": there is a Greek god Hades.
The god Poseidon was the Greek god of the ocean.
the greek god hermes the god of messages
Poseidan the Greek god was related to Hades the Greek god!
He is a Greek God.
He is the Greek god of the sun.