Nebula
From Starsonata Wiki
Although they serve no other purpose than as fanciful decorations, nebulae nevertheless are a common sight throughout the game and take many forms; some as amorphous blobs, others as gaseous circles splashed with color, and even a few that appear as wormholes. Many emit auras, generally providing double resistances, but other, more interesting auras are seen emitted by nebulae in dungeons that usually affect only the AI.