Blazing Wheel

The Blazing Wheel is an indestructible Enemy found in the Dungeon. It appears to be a ring of fire, traveling along the walls and floors of the Dungeon. Blazing Wheels move quicker than most Dungeon enemies and produce light. They appear in areas that have a Dungeon Brick Wall background.

Movement

 * They spawn and despawn off-screen, like any other enemy.
 * They will go through open doors, but not through closed doors.
 * They travel through Platforms, not along them.
 * If you remove all of the blocks the Blazing Wheel is spinning on, it will fly towards the nearest wall.
 * If you surround a Blazing Wheel with blocks until there are only 2-3 tiles of space for it to maneuver, it will despawn.
 * Blazing Wheels will go outside of the Dungeon, however it is very rare, and you must follow it until it does.
 * They move at a surprisingly fast speed, making it harder to dodge them.

Tips

 * A useful way to avoid being hit by the Blazing Wheel is to use a Multi Hook to suspend yourself in midair, rather than standing still on a Dungeon surface.
 * To avoid the Blazing Wheel's attack, look for its light in dark areas, move as far away as possible, then jump or avoid it if you don't want to lose health.

Trivia

 * The Blazing Wheel, along with the Spike Ball, the True Eye of Cthulhu, and Golem's head in his second stage are the only four invincible enemies in Terraria.
 * Although the Blazing Wheel cannot be damaged, it has most of the statistics of a normal enemy, including a death sound, a hit sound, defense, and immunities to a few debuffs.
 * The Blazing Wheel is likely based off the Hothead from the Mario franchise. It moves in similar motions when climbing on walls and ceilings and is also based around a fire theme.

History
Flammenrad 불타는 바퀴 Blazing Wheel Огненное колесо 烈焰火轮