Mud Block

A Mud Block is a Dirt-like Block that can be found Underground and crafted in Water while holding a Dirt Block. Mushroom Grass Seeds and Jungle Grass Seeds can only grow on mud.

When placing a Jungle Grass Seed on a Mud Block at below a certain depth (700ft in small worlds, 1,000 feet on large worlds), you can create an Underground Jungle. Mushroom Grass Seeds will only grow at below 0ft.

Crafting recipe from dirt was added because Corruption at hardmode can very slowly turn Mud Blocks into Dirt Blocks and therefore spread through.