🪸 Seagrass-like Block

Seagrass-like Block is permanently waterlogged, like vanilla seagrass. It has no waterlogged property — the block is always filled with water.

Can only be placed in water (a full water block); placement anywhere else is denied.
A bucket can neither take water out of it nor pour water into it.
Water re-flows from its position whenever a neighbor changes.

warning

Pair this behavior with fluid_state: water, otherwise the block is not treated as a water source: water will not flow from it, entities inside it are not considered to be in water, and breaking it leaves air instead of water.

Whether water actually flows out of the block depends on its collision shape: thin plants (e.g. auto_state: kelp) let water through, while a full-block collision seals the water inside — the same rule vanilla uses for waterlogged leaves.

Example

blocks:
  default:water_grass:
    behavior:
      type: seagrass_like_block
    settings:
      fluid_state: water      # treat this block as a water source
    states:
      appearances:
        default:
          auto_state: kelp    # thin collision shape — water can flow out
          model:
            path: "minecraft:block/custom/water_grass"

tip

For a toggleable waterlogged block (like a slab or stairs, which can also exist in a dry state), define a waterlogged boolean property instead — the waterlogged behavior is applied automatically. Set fluid_state: water on the waterlogged=true variant via variant settings.

Example​

Example