Leeches are found in the oceans and in water next to swamps. If a creature comes within a one tile range of the leech, they will have the leech stuck to their bodies and the leech will do damage daily.
Leeches are bright yellow with a purple mouth. Leeches are completely immobile, meaning they are unable to move unless attached to a creature; unless you are on the Killer or Jungle island. Leeches on those islands will move around the water every time your creatures move in an attempt to latch onto a creature.
Removing a leech is the same as curing bleeding. The leeched creature has to be within a one tile range of another creature who will remove the leech. Doing this takes one action point, but the leech becomes a food point.
If a creature stands near the leech, it is possible to "harvest" the leech without getting any damage.It requires atleast one strength and one action point
Even after removing a leech, the creature will sometimes still receive damage until it passes away. Some Niche-playing YouTubers like to call it "The Leech Disease" for story purposes.