Leech has 60 health and spawns in the swamps.
It resists poison; fire and spirit do nothing to it at all. Blunt, slash and pierce land at full damage, so that is what to bring.
Its only attack is bite attack, 70 poison and 20 pierce.
Some of what it throws is elemental, so poison resistance is worth having.
Of everything craftable, 
Frostfire Crossbow, 
Thunderblood Crossbow and 
Lightning Strike put the most damage through what it resists.
It always drops 
Bloodbag.
Leech is an aquatic worm of the Swamp with 60 health that lies in standing water and bites for 20 pierce and 70 poison in a 1.5 meter arc every 2 seconds. It is immune to fire and spirit and resistant to poison, so fire arrows are wasted on it and the poison it inflicts cannot be turned back on it. It spawns day and night wherever the swamp holds water, which is most of it. Every kill drops one Bloodbag, with the 
Leech Trophy at 10 percent.
Never wade where you can walk. Their bite stacks 70 poison on top of the swamp's other miseries, so keep 
Poison Resistance Mead running and clear them from dry land with a bow. Their bloodbags brew into the meads you will want anyway.
| Where | Roll | Group | Conditions |
|---|---|---|---|
| Swamp | 50% every 200 s, max 10 near you | 1 | altitude -3 to -0.1 m · up to ★★ |
Each 64 m zone keeps its own timer per entry and rolls the chance once per interval while loaded; a zone never loaded before rolls the moment you arrive. The spawn lands 40 to 80 m from a player, never inside a base unless noted, and "max near you" counts the loaded area around that zone. Dungeon and camp spawners are separate and not counted here.
With devcommands enabled, this spawns Leech in front of you. The third number is the level: 3 spawns a 2-star.
Creature ID: Leech · all console commands and IDs