Change their voices by "feeding" them different molecules (e.g., Glucose makes them high-pitched/fast; Antibiotics make them slow/raspy).

: Feeding the bacteria donuts would cause them to procreate, allowing you to have up to six (or eight in older versions) Johns on screen at once. Interactions : Tickle : Making them laugh. Syringe : Injecting them to trigger a "laughter frenzy".