The killer droids, short for merciless hunter-killer droids, were introduced in Number 2135: They Also Serve Drinks. One of them was modified in Number 2165: Fond Farewells as a security droid designed for hugging.
| Characters | |
|---|---|
| Coffee of Doom | Smif College |
| The Secret Bakery | Union Robotics |
| The Space Station | AI rights nonprofit |
|
|
| The Horrible Revelation | Robot-Fighting Ring |
| Cubetown | |
| Parents | |
| Other | |
| Robots | |
| Minor | Filler strips |
| Unnamed/unseen characters | |