Use Water and Lava in Composite Blocks

Waterlogging Composite Spaces

You can fill composite blocks with water while keeping decorations intact:

1. Hold a water bucket

2. Aim at a specific part within a composite block

3. Right-click to waterlog that piece

4. The water fills only that part's space; other blocks remain dry

Creating Obsidian Reactions

When lava-logged and water-logged parts touch inside the same cell, they create obsidian:

1. Place a lava-logged block in a composite space

2. Add a water-logged block to the same cell

3. They react and form an obsidian part

4. Toggle reactions with the /gamerule no_more_gap:do_lava_logging_reactions command if needed

Removing Liquids

Use an empty bucket on a liquid-filled part to drain it. This works for both water and lava, giving you precise control over your build's hydrology without affecting neighboring blocks.