The Trabuco was the ultimate siege engine of the medieval era. It could deliver a number of different payloads from a huge distance away. Often giant stones were used in Trabuco’s which could bring down enemy walls and other fortifications. They could also be loaded with ceramic firebombs which were fired on enemy formations and set them all on fire. Sometimes they would fire dead animals, or even people, who had died from a disease. The hope was to infect the enemy and kill or incapacitate them that way.
Trabuco’s were used across Asia and Europe by just about every army because it was such a leap forward in technology. It was only when gunpowder was invented that the use of Trabuco’s fell by the wayside. They were invented in China in the 4th century B.C. They were based on the concept of a slingshot writ large. The Avar people, who were made up of nomadic tribes, spread the use of this siege weapon west. The eventually ended up in what is now Hungary. The Byzantine Romans were the first culture in Europe to begin using the Trabuco on their enemies according to infopedia.pt. From there it spread to other armies on this continent.
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There is an arm at the top of a Trabuco which is much longer on one end than the other. A sling is attached to the endpoint of the longer slide. The sling is filled with the chosen projectile and then an arm is removed. When the arm is removed the arm shoots straight up which causes the payload to be thrust out of the sling and at the target. While early versions of the Trabuco could fire a 400-pound boulder later versions were even more terrifying to the enemy because they could fire off 1-ton boulders.
Even after gunpowder mostly replaced the Trabuco it was still sometimes used. This happened most often when an army ran out of gunpowder or needed to conserve their stores. An example of this occurred in 1521 When Hernán Cortés built one to help his Spanish army siege the city of Tenochtitlan.