Titanus

Titanus is a large city built on a platform surrounding a supermassive spinning black hole surrounded by a sphere of mirrors. The supermassive black hole provides the city infinite energy, creating what many call a utopia. There are countless alien species living in Titanus, all in a fragile peace, none willing to start a war in fear that the mirror sphere surrounding the black hole will cease to release energy, resulting in a massive super nova explosion, the largest explosion in the galaxy.