Morb is a critter that spawns from neglected outhouses and appears as a small, usually passive creature that interacts with waste and the colony environment. Morbs wander in a straight direction until blocked, then reverse course; they can jump two-tile-high walls and cross single-tile gaps, and like other critters they can become trapped inside doors and Mesh Tiles. Morbs are normally non-hostile and will attempt to flee when attacked.
Morbs periodically emit a cloud of 200 g Polluted Oxygen contaminated with 200 Slimelung germs when specific conditions are met: the tile is not vacuum or occupied by liquid, pressure is below 1000 g, and the Morb arrived on that tile on its last movement. An emission animation may play if the second tile above is unblocked, though the animation is not required for the emission to occur.
If an outhouse is filled, not disabled, and left unemptied for two cycles, a Morb will spawn nearby. Morbs can also be intentionally spawned by toggling (disabling and enabling) an outhouse or by reloading the game, making refilling unnecessary for deliberate generation.
On rare occasion Morbs enter a special enraged state known as "morbing." This has a very low base chance of occurring once per cycle (0.1%). When a Morb morbs, all Morbs in the same room will also morb. Morbing Morbs become aggressive and will attempt to bite duplicants. If a duplicant is bitten while infected, they receive roughly 1 morbillion germs of the disease Morbius Crohn; if left untreated, the disease will turn the duplicant into a Glorb after three cycles. Glorbs are functionally identical to Morbs but are permanently morbing and thus continuously hostile; a Glorb also shows a visual appearance based on the duplicant that transformed into it. Morbs produced by a duplicant-turned-Glorb cannot infect other duplicants unless they in turn bite their creator Glorb back.
Practical notes for handling Morbs:
Prevent Morb spawns by keeping outhouses emptied or by disabling outhouses that are deliberately left filled. Regular waste servicing stops automatic spawning.
Avoid letting Morbs roam inside living quarters or high-traffic areas because of slimelung emissions; emissions create Polluted Oxygen and spread germs.
If morbing occurs, isolate the room immediately and either kill or evacuate duplicants; morbing can cascade to all Morbs in the same room.
Treat any Morbius Crohn infections promptly with appropriate medical care to prevent transformation into a Glorb.
Morbs can be trapped with standard critter traps or blocked with doors/tiles, but be aware they can jump two-tile obstacles and may become stuck in door tiles.
