Dreadnought, also known as missile ATR-4107, was an automated Cardassian weapon capable of unleashing massive destruction. Although officially referred to as a missile, it can also be considered a completely autonomous warship in its own right. It was a warp-capable vessel carrying 1,000 kilograms of matter and 1,000 kilograms of antimatter — enough to destroy a small moon. The missile also carried a large cache of conventional weaponry, including disruptors, prototype quantum torpedoes, a thoron shock emitter and a plasma spread. On board was a sophisticated computer system that could predict and counter hostile actions.

In late 2370, the Cardassians deployed the missile to destroy a Maquis munitions base on the asteroid Alpha 441 in the Demilitarized Zone. Although the Maquis threw every weapon available at the missile, it proved unstoppable due to the combined benefits of its strong defenses and its advanced computer. However, the missile failed to detonate upon reaching its target — the Cardassians had used an old-fashioned kinetic detonator in the design, which malfunctioned; the missile simply drifted into orbit around the planetoid instead of destroying it.

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