One of the popular acts they do is called sword swallowing. This is a very dangerous stunt were they put a razor sharp sword down their throat like its nothing. This is an ancient skill in which the performer passes a sword through the mouth and down the esophagus to the stomach. This is not swallowing in the traditional sense; the natural processes that constitute swallowing do not take place, but are repressed on order to keep the passage from the mouth to the stomach open for the sword. If not done right, you will cut your stomach lining, esophagus etc and bleed to death. This has happened before and will continue to happen as long as people perform that ancient stunt.
Another one of the crowd's favorite, is fire breathing. Fire breathing, is the act of creating a fireball by breathing a fine mist of fuel over an open flame. The proper technique and correct fuel create the illusion of danger to enhance the novelty of fire breathing, while reducing the risk to health and safety. When using the correct fuel, it will only light when sprayed into a fine mist increasing the surface area of the fuel so that the fuel/oxygen/heat ratio is balanced enough to cause combustion. The recommended fuel to use is ultra pure clear unscented lamp oil. There is great risk of doing this, the person can ingest it, get it into their eyes. Improper technique using the proper fuel can still risk mist inhalation, which may cause symptoms such as death,severe burns,