The Utwig Bomb (a misnomer, since the Utwig only found, never built such a device) was one of the most fearsome weapons in known space. This device releases a large amount of antimatter upon detonation, on average annihilating all matter within a 500-km radius, creating a powerful explosion whose blast radius extends for several AU. The energy released by the explosion is great enough to completely disperse a small moon into dust or to blast a larger planetary object into chunks; scientists speculate that planetary engineering may have been the primary purpose of the device, since as a weapon of war it is highly dangerous and imprecise.
At least two examples of such weapons have been found. The first known to the Alliance was found by the Shofixti and kept as a secret weapon, an ultimate version of the Glory Device they favored as a final option in combat. When the Shofixti were on the brink of destruction at the hands of the Hierarchy, they lowered the Bomb into the outer layers of their home star and activated it, causing an immense storm of solar flares similar to a minor nova. The flood of radiation destroyed or rendered inoperative all ships occupying the system at the time, killing all life within them as well as burning out all life on the Shofixti homeworld Kyabetsu. The Ur-Quan Kzer-Za fleet was reduced in size about 30 percent from that battle alone, giving them a crucial disadvantage in the coming Doctrinal Conflict.
The second device found by the Alliance was discovered by The Captain in his dealings with the Utwig. The Utwig related to him how they had discovered an identical Bomb device in a damaged protective container in an abandoned Precursor supply depot. Their superstitions about the Ultron led them to believe that the sheer destructive power of the Bomb had been granted to them as part of their history-shaping destiny, and when the Druuge came to trade the Ultron for the Bomb they avoided doing so, whether because of a clever ruse or because of the guidance of the Ultron none can say. When the Ultron was lost and the Utwig sank into a deep depression, they reasoned that the purpose of the Bomb may have been to allow them to commit painless suicide in atonement for their act, but then wondered if a greater atonement might not be to live in misery and guilt for their foolish destruction of the Ultron. While weighing this decision, they kept the Bomb in safekeeping on a special world reserved for that purpose, to protect innocent worlds from an accidental detonation.
When The Captain came to the Utwig, seeking a device powerful enough to destroy the Ur-Quan's Sa-Matra, he had to repair the Ultron for the Utwig before he — or the Ultron itself, according to the Utwig — convinced them to let him hold stewardship over it. Unfortunately, while The Captain and the Utwig Proctors were in negotiation, the Druuge had meanwhile attacked the Bomb world, Zeta Hyades VIb, and seized control of it. Fortunately, the Utwig had wisely masked the Bomb's location against the Druuge's scanners, and The Captain was able to defeat the Druuge and recover the Bomb before they could find it. However, even the Bomb in its unmodified state could not generate an explosion powerful enough to guarantee the irrevocable destruction of the Precursor-engineered Sa-Matra. Luckily, the Bomb's manufacture bore some similarities to Chenjesu manufacturing, so that the Chmmr were able to use their technology to couple the Bomb to The Flagship's energy generation systems, greatly augmenting its power. It was the sacrifice of The Flagship, detonating the Bomb inside the Sa-Matra's docking bay, that finally destroyed the Ur-Quan's Great Prize and ended the war.
In physical appearance, the Bomb was a squat black cylinder, the size of a small ground-car. On it was written a very recognizable Precursor inscription, repeated over and over all over its surface; though it has not been completely translated, it seems obvious that the message is a warning. Though human scientists deemed it unsafe to conduct many tests with the device, the level of radiation output detected near it suggests a powerful, constantly running energy generation system similar in capacity to The Flagship's own engines.