Mud Blocks are a very common block type that comprises the majority of the Jungle, Underground Jungle, and Glowing Mushroom biome. Mud Blocks may be covered by Jungle or Mushroom grass on any side, which can only grow and spread on mud, and can be planted with Jungle Grass Seeds and Mushroom Grass Seeds, respectively.
- In Hardmode, the evil biomes are capable of converting nearby Mud Blocks to Dirt Blocks, and Chlorophyte Ore is capable of doing the reverse. While the evil biomes can also convert Mud Blocks covered by Jungle grass into a Dirt Block with the respective evil grass type, Mud Blocks with Mushroom grass can never be converted.
- Thrown Water and the Clentaminator similarly convert Mud Blocks covered with Jungle/Mushroom grass. Bare Mud Blocks will not be converted by these items, unless there is a grass block of the target biome (e.g. a Crimson grass block when using Blood Water/Red Solution) directly adjacent to it.
- Desktop 1.2: Stack limit was raised from 250 to 999.
- Desktop 1.0.6: Removed chance to fall when struck (reverting the earlier change).
- Desktop 1.0.5: Added chance to fall when struck.
- Desktop-Release: Introduced.
- Console-Release: Introduced.
- Switch 1.0.711.6: Introduced.
- Mobile-Release: Introduced.
- 3DS-Release: Introduced.