World Devastators are unique among superweapons in that they do not merely destroy planets or ships, but consume them. Giant tractor beams literally rip apart a planet's surface to feed the Devastator's huge molecular furnace, converting these raw materials into energy and various alloys to power not only this massive engine of destruction, but feed its droid, starfighter, and vehicle foundries as well. World Devastators can also add armor, defenses, and other features to themselves from the consumed material. The first mission of a new World Devastator is to consume asteroid fields or other shattered planetoids to produce weapons, armor, and basic defenses. It is noteworthy that, given sufficient materials to consume, there is no theoretical upper limit to the size of a World Devastator .

World Devastators are often deployed in groups to facilitate the breaking up and consumption of a planet. This process can take months, intensifying the horrible psychological impact on the besieged world. The vessels often target cities and other artificial facilities first as they are rich in useful alloys and minerals.

These destructive engines are large and far from helpless. During the attack on Mon Calamari, the lead vessel, Silencer 7, was armed with over 100 heavy turbolasers, 200 blaster cannons, 80 proton torpedo tubes, 15 ion cannon, and 15 tractor beams. The massive Devastator was 3200 meters in length and 1500 meters tall, far larger than an Imperial Star Destroyer, and it was constantly growing. The heavy armor and shields of the World Devastators were impervious to even concentrated turbolaser fire, making these harbingers of doom virtually unstoppable.

Fearing these massive weapons might be used against him, the reborn Emperor Palpatine fitted every World Devastator with a Master Control Signal allowing him full remote control. When Luke Skywalker apprenticed himself to Palpatine, he was made Supreme Commander of the Imperial Fleet, and given access to the MCS. The traitorous Skywalker betrayed the Emperor and all but one of the World Devastators, was destroyed 10 ABY, when R2-D2 used the Emperor's codes to make the Devastators attacking Mon Calamari turn on one another. The rest were subsequently ordered to shut down and were destroyed. A single unknown Devastator was captured by New Republic forces over Da Soocha V as it drifted silently in orbit. Its fate is unknown.