Fouled potions and alchemical waste can give rise to Sewer Plague, which incubates in sewers and refuse heaps and is sometimes transmitted by creatures that dwell in such areas, including otyughs and rats. Any Humanoid that is wounded by a creature that carries the contagion or that comes into contact with contaminated filth or offal must succeed on a DC 11 CON Saving Throw or become infected with Sewer Plague. A creature suffers the following effects 1d4 days after infection: **Failure by 5 or more.** If a creature fails the save by 5 or more, the symptoms begin after 1d4 hours rather than days. **Fatigue.** The creature gains 1 [[Exhaustion]] level. **Weakness.** While the creature has any [[Exhaustion]] levels, it regains only half the normal number of Hit Points from spending Hit Point Dice. **Restlessness.** While the creature has any [[Exhaustion]] levels, finishing a Long Rest neither restores lost Hit Points nor reduces the creature's [[Exhaustion]] level. **Fighting the Contagion.** Daily at Dawn, an infected creature makes a DC 11 CON saving throw. On a failed save, the creature gains 1 [[Exhaustion]] level as its fatigue worsens. On a successful save, the creature's [[Exhaustion]] level decreases by 1. If the creature's [[Exhaustion]] level is reduced to 0, the Disease ends on the creature.