Nebula Floater

The Nebula Floater is a Hardmode, post-Lunatic Cultist flying enemy that spawns near the Nebula Pillar during the Lunar Events. It periodically spawns miniature eyes that float around it. Its main attack is either ramming into the player, or by distancing itself and proceeding to shoot a pink Nebula Laser from one of its followers at you, dealing significant amounts of damage. It will also try to teleport around the player while firing its laser, appearing to do this more often in Expert Mode. It is one of the enemies of the Nebula Pillar event that must be paid attention to. They are somewhat common and in groups can overwhelm the player.

Tips

 * Using weapons that are good for crowd control can come in handy when dealing with large groups of Nebula Floaters. If you've already defeated the Vortex Pillar, the Vortex Beater with Chlorophyte Bullets would be a great weapon of choice.
 * The lasers leave a trail on their path, making it easy to tell where they're shooting you from. These are not to be confused with the lines coming from slain enemies, which are yellow and red in color.
 * Nebula Floaters sometimes teleport when hit, so using a high-damage weapon (such as a Sniper Rifle) may be advisable.
 * According to Re-Logic, "On Nebula Floaters, homing weapons are actually NOT always the best solution. Nebula Floaters teleport randomly on hit and have a 'counter shot', which means that free floating minions or homing attacks may cause them to spontaneously teleport and shoot you without warning."

Trivia

 * The appearance of the Nebula Floater closely resembles the Brain of Cthulhu.