Poseidon seems miffed at being tricked by the illusion of this place. He is clearly not pleased. Not pleased at all.
He tries to conjure up some waves but he found out that he could not use any of his power. He look at Hades
Hades only smile
"My powers?"
"Tartarus is like a Void. It has the essence of the Other Side of Creation"
"Everything that exist is not Tartarus. Everything that is opposite of that is Tartarus. Yin and Yang, Light and Dark, Good and Evil, Life and Death, Creation and Destruction. Tartarus is the one in between. The Nullifier. The Void that Nullifies all things."
"A Void?"
"A Void"
For a moment Poseidon thought of something. Hades chuckles. Some things his brother did not learn
It is quite the great feeling of knowing something that others did not.
Poseidon then sighed
Clearly, when Hades was talking before, there is an enlightenment that passes by his mind.