Bacteria

Bacteria are invisible organisms that cause disease in the Creatures series.

In Creatures 1, they randomly infect a norn or grendel with one antigen. Later, after the bacteria themselves have evolved, they randomly infect a norn or grendel with an unknown toxin, which may include more than one antigen, one or more histamines, and other toxins. Players that wish to avoid this evolution can export their norns and reset their world using the Emergency Kit.

In Creatures 2, there are no true bacteria, per se, as the game chooses a creature at random to infect.

In Creatures 3, you cannot see the bacteria without aid. The Hoverdoc can provide this in the form of a bacteria-detection spray, or you can use VisiBug by Hausmouse. The HoverDoc and Containment Chamber can also provide bacteria-killing spray. In DS, you can use the Bacteria Button by Moe to see the bacteria. To remove bacteria using the CAOS Command Line, see C3/DS_CAOS_Codes. The bacteria nerf patch changes several aspects of bacteria in the games.

In Docking Station, the vast majority of bacteria appears in the Workshop.

In Creatures Village, the haunted forest and dungeon are the most bacteria-laden part of the world, and the house is bacteria-free.