Leech (5e Creature)
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Tiny beast, unaligned
Amphibious. The leech can breathe air and water.
Salt Susceptibility. For every handful of salt thrown on the leech, it takes 3 (1d6) acid damage.
Bite. Melee Weapon Attack: +2 to hit, reach 5 ft., one creature. Hit: 1 piercing damage, and the leech attaches to the target. While attached, the leech doesn't attack. Instead, at the start of each of the leech's turns, the target loses 1 hit point due to blood loss.
Leeches are horrible little worm-like creatures that derive sustenance by draining the blood of larger animals. They tend to live in swamps or freshwater, though some types of leeches live on land. Salt burns the flesh of a leech, and many explorers that travel through swampy areas take a bag of salt with them.