Fluid Interaction Tweaker

The mod is a CraftTweaker and GroovyScript addon for Minecraft Forge 1.12.2. It does not change how vanilla water and lava interact. Instead it adds a separate, general system of fluid interactions that scripts can define and that the mod runs when the conditions are met. Three reaction types are covered: a fluid turning a touching block into something else, a fluid turning a block into another block when the two touch, and a block changing when a fluid reaches it. Each reaction can trigger a series of events, and the list of available events includes placing a block.

Because it is a scripting addon, the mod is used from script files rather than from an in-game interface. Client and server both need it, so the server and every player install the same build. Fluid Interaction Tweaker is released under the MIT License and is open source. Its source code, issue tracker and wiki are public. Files exist only for Forge and only for 1.12.2, with 1.5.4 as the latest file, published 2025-07-04. The first release came out on 2025-04-14. The mod is categorized as a Library and Game mechanics mod, and it is one of 228 Library mods that have Forge files for 1.12.2.