Throughout the Dragon Ball saga, there is no shortage of increasingly intense kills as every villain the Z Fighters face just keep getting worse–both in terms of incredibly high power levels and their levels of evil. However, there is one villain who stands above the rest as being the most terrifying of the Dragon Ball Z era, one who earned that title with his exhibition of the grossest kill in Dragon Ball history–and that villain is Cell.
Upon his introduction, Cell proved to be a formidable force the likes of which the Z Fighters had never faced before, and his appearance couldn’t have come at a worse time. At this point in Dragon Ball continuity, Androids 16, 17, and 18 had just been activated and were on a mission to kill Goku as per their original programming. While they weren’t as motivated to kill him as quickly as they maybe should have been, the Androids proved to be immensely powerful as they were as strong as a Super Saiyan with unlimited energy, allowing them to fight forever and not get tired. However, just as the Z Fighters were coming up with a way to stop them and save Goku’s life (who was suffering from a heart condition at the time), Cell emerges and only adds to the horror of their current situation.
In Dragon Ball chapter 361 by Akira Toriyama, Piccolo–who had just rejoined with Kami and became the most powerful fighter on Earth at that time–sensed a huge power level and decided to check out its source. Piccolo flew to the heart of a city, one that was usually buzzing with life, but was now desolate and dead. Loose articles of clothing lay on the ground as if the people inside of them melted into nothing. Then, emerging from the shadows, came Cell–a bug-like creature with giant wings, green chitinous skin, and a long deadly tail. In his grasp, Cell had a single human who was begging for his life, pleading with Piccolo to save him before he was killed by this mysterious monster. Before Piccolo has a chance to react, however, Cell stabs the man in the back with his tail and sucks the life force out of him until there is nothing left but another set of clothing littering the vacant streets.
While Cell’s ability to suck the life out of people may not seem like a big deal to the Z Fighters as they have battled planet-destroying warriors and intergalactic tyrants, his presence on Earth is unbelievably terrifying from the perspective of normal humans. Aside from King Piccolo (and one city obliterated by Nappa) humanity has been spared the cruelty of Dragon Ball’s villains. When Cell makes his debut, however, he targets regular humans before challenging the Z Fighters–wiping out entire cities by draining people one-by-one. Based on his appearance, his virtual indestructibility, and the manner in which he kills people, Cell is a legitimate horror movie monster. A giant bug-like creature stalking powerless humans to drain them of their life force until there's nothing left of them–with the power to do this to entire cities with no one around strong enough to stop him–is a horrifying concept that other Dragon Ball villains simply can’t compete with.
The only other villain in the Dragon Ball mythos who would arguably outmatch Cell in terms of sheer horror is Dragon Ball Super’s Moro as he drains the life force of entire planets and uses the energy of billions of dead creatures to make himself virtually unstoppable. However, while Moro’s methods are terrifying on a cosmic scale, Cell hunts his victims one at a time, and his way of draining people is a much more personal experience of helplessness and dread. For this reason–which presented itself as a kill that was equal parts terrifying and disgusting–Cell is easily the scariest villain in Dragon Ball history.