The Phantom Galaxy is a very distant irregular dwarf galaxy, 21.03 billion lightyears from the Milky Way, making it one of the most distant galaxies observed, although not as far as the Stardust Dwarf Galaxy or Coark. It is very small, only being 7246.42 lightyears in diameter and is estimated to contain 250 million stars.
The galaxy was named for its ghostly appearance and eerie bluish glow. It mostly consists of large hot blue stars, giving it its colour.
Life is probably a rare occurrence in this galaxy, intelligent life even more so. Any civilisations in the Phantom Galaxy would have no problem conquering it due to it's small size and would likely be confined to it because of how isolated it is.
The Phantom Galaxy is far beyond the reach of any wormhole drive so travelling here is not possible.