Mud is a block found in mangrove swamps or created by using a water bottle on Dirt, Coarse Dirt, or Rooted Dirt.

Mud can be used to craft Packed Mud and Muddy Mangrove Roots or converted into Clay when placed above a block with Pointed Dripstone underneath. Unlike solid blocks, entities standing on Mud sink slightly into it, but it does not slow movement. Sand and other falling blocks break when landing on Mud, and hoppers can collect items through it. Mud can also be found in Trail Ruins and some Trial Chamber entrances.