The Tarantula is a robotic sentry turret used by the Imperial Guard and Space Marines to defend strategic positions. Utilizing simple logic engines and infused with a machine spirit, the Tarantula can function without needing to be controlled by a human gunner. Commonly fitted with either twin-linked lascannons or heavy bolters, the Tarantula offers a significant deterrent to both enemy armor and infantry waves. However, it is not intelligent enough to actually choose its targets - instead only prioritizing the closest threat in range.
Beloved by the Imperial Guard, because it's an automated gun turret defending them on the front lines, and they don't even need to be in harm's way.