Nebulas are clouded areas of space. Nebulas restrict the view of the player. The player cannot see inside of a nebula from the outside, and they cannot see outside from the inside. They can only see two jump points ahead of them. Planets and stars inside of nebulas are usually dead, dying or terrifyingly evolved. Dying planets are covered in toxic water, frequently bathed in acid rain and there are few creatures or plant life. Dead planets are entirely void of life - these are already in the game called Barren planets. Evolved planets survived the nebula by evolving to live inside of it. The creatures are more deadlier, the plant life can be carnivorous and the water is toxic. Civilisations are either destroyed because of the nebula, or are science facilities lucky enough to be prepared to survive a life inside of a nebula.
I can't help but also picture highly futuristic civilizations resembling the virtual reality in Adventure time thriving in Nebulae, with colorful celestial clouds everywhere!
