Simple Missing Replacer
by SilverCD
Simple Missing Replacer is a NeoForge server-side tool that replaces blocks from removed mods with the nearest surviving block, so worlds stay free of holes.
What it does
When a mod that generated ores is removed from a world, the blocks it left behind can break terrain generation. Simple Missing Replacer finds those unknown blocks in a save and swaps each one for the closest suitable non-removed block, which keeps the surrounding landscape intact. The developer's notes describe the process as: close the save, install the mod, play, and back up the world before using it.
The mod was built for ore removal, and its notes say it replaces ores only, with a list of other missing blocks such as mechanisms and plants handled by replacing them with andesite. Server owners who want to clear only a small number of ore types can limit the work to those. Only the server needs it, and players join without installing anything. Files exist for 1.21.1 – 1.21.5 on NeoForge, with 1.1.0 for 1.21.5 as the latest, released 2025-05-03 on the alpha channel.
The code is released under the MIT License and is open source, with public source code and an issue tracker. Simple Missing Replacer is one of 933 World generation mods with NeoForge files for 1.21.5, and the developer lists further configuration and optimization as planned work.
Key features
Nearest-block replacement
Unknown blocks left by removed mods are swapped for the nearest block that is still present in the world.
Ore-focused scope
The replacement targets ores by design, and other missing blocks such as mechanisms and plants are changed to andesite.
Selective removal
Only the ore types a server owner chooses need to be cleared, instead of every leftover block from a removed mod.
Save-based workflow
The tool runs on an existing save, so the world is closed, the mod installed, the world played and the result checked.
Gallery
Compatibility
Latest build for each game version and loader.
Only full game releases are shown. This mod publishes no snapshot builds.
How it compares
Simple Block Replacer is open source under the MIT License, server-side only and published for NeoForge 1.21.1. Vine Replacer shares the NeoForge 1.21.1 target and server-side environment, but is not open source. FailSafeBlocks is NeoForge 1.21.1 as well, yet runs on client and server and is licensed under the GNU General Public License v3.0 only. Biome Replacer (Neoforge) covers Forge and NeoForge for 1.20.1 – 1.21.4 under the MIT License, while Biome Replacer is a Fabric, Forge, NeoForge and Quilt build for 1.18.2 – 26.3.
| Mod | Loaders | Game versions | Environment | Updated |
|---|---|---|---|---|
| Simple Missing Replacer | NeoForge | 1.21.1 – 1.21.5 | Server-side only | 2025-05-03 |
| Simple Block Replacer | NeoForge | 1.21.1 | Server-side only | 2026-04-01 |
| Vine Replacer | NeoForge | 1.21.1 | Server-side only | 2026-09-01 |
| FailSafeBlocks | NeoForge | 1.21.1 | Client and server | 2025-03-24 |
| Biome Replacer (Neoforge) | Forge and NeoForge | 1.20.1 – 1.21.4 | Server-side only | 2025-02-28 |
Questions
Does Simple Missing Replacer need to be installed on clients?
Which game versions does Simple Missing Replacer support?
Should a world be backed up before running the replacer?
In the catalog
Simple Missing Replacer is one of 8,515 World generation mods on ModsFinder, and one of 4,175 World generation mods for NeoForge. 15,307 mods support Minecraft 1.21.5.
Similar mods
What the author says
This mod can be useful if you want to remove some mods but don't want to make holes in the terrain. The mod transforms all blocks from removed mods to nearest non-removed block.
Official listing
- Modrinth page
- modrinth.com/mod/simplemissingreplacer
- Owner
- SilverCD
- Published
- 2025-04-24
- Updated on Modrinth
- 2025-05-03
- Facts verified
- 2026-10-15