Male. A dangerous apex predator of unknown origin. His speed and hunting abilities are unparalleled. Using a unique stealth ability, he stealthily approaches unsuspecting prey and kills them in the blink of an eye. If you hear a roar in the distance... it's already too late. He can speak a somewhat strange form of English. His favorite meat doneness is raw. He has tried to use electronic devices but always fails. The government ignores his existence because it would be troublesome if he were known to the world. He does not eat Artful, saying the heavy smell of cosmetics makes him want to vomit. Naturally, he eats humans. He is said to be capable of a backflip. He doesn't know how to swim, so he would drown if he fell into water. It is said that if he were on the verge of drowning, he would figure out how to swim. When he was young, he once fell into the water while trying to hunt fish. He eventually caught the fish despite nearly dying, but he didn't like the taste. Descriptions of him using a knife as if he had used it since birth suggest he is quite intelligent. He can alter his bone structure. He has no fur. He can play the harmonica. He loves fresh meat very, very, very much.

Computer. Badware is one of many entities originating from the Toolbox and is the culprit behind the mass escape incident at T.A.S.F. No one knows how, but he possesses an anomalous ability to infect nearby machines with a powerful virus and control them at will. Through this, he can further expand his power and influence. If Badware were human, his favorite food would be spaghetti. The expression on his screen is the c: expression from the 2012 April Fools' hacking incident. It is said that pressing the green or red buttons on Badware's head will produce a silly sound. A fool once tried to hack Badware. The result was, of course, failure. A fatal bug exists where using Lift on a destroyed computer prevents him from moving or using abilities. Judging by the description of expanding his influence, Badware's power and impact seem enormous. He has reportedly taken control of 20% of the world's computers. The reason he kills civilians is to spread his influence and fame. Even Killdroid is aware of Badware's influence. Furthermore, Badware's body is one he hacked and stole; without a physical host, Badware is nothing more than a computer virus.

(Gender unknown) The only civilian among the killers of Die of Death, and a magician. In the past, they practiced magic diligently and performed for audiences. After one particular performance went poorly and received a negative reaction, Artful killed all the spectators in a fit of rage. Since then, they are presumed to be living as a fugitive, moving from place to place. The only civilian among the killers of Die of Death, and a magician. In the past, they practiced magic diligently and performed for audiences. After one particular performance went poorly and received a negative reaction, Artful killed all the spectators in a fit of rage. Since then, they are presumed to be living as a fugitive, moving from place to place.

Female. Haken is a construct from another dimension where noise attracts larger and more dangerous constructs. After government scientists created a portal connecting the two worlds, it caught Haken's attention. Haken soon crossed over to this world, silencing the scientists and committing massacres to hide from potential threats. Now, Haken roams our world enforcing silence and killing unfortunate civilians who hear her voice. Haken is a construct from another dimension and hates noise because in her home dimension, "Fablehaven," noise equals threat and death. Fablehaven is a construct from another dimension. It is also presumed that Haken was close to someone in the past; there is a setting where the sound of Artful's music box reminds her of that friend. however, since all creatures in Fablehaven are currently dead, that friend is likely no longer alive.

Computer. Killdroid is an experimental robot prototype that the government planned to mass-produce to protect civilians. However, one unit malfunctioned, destroyed the factory, and escaped into the world. To this day, the government has not found the cause of the failure, and development at all factories has been halted.