Mustard Virus by Forge Labs Server Hosting

We recommend 5 GB. The pack has only 34 mods on Forge 1.12.2, so the mods themselves are cheap to load. What eats server time is the zombie population, especially when a crowd gathers in one street. If your group plays long sessions near dense parts of the map, add a gigabyte, and use spark to confirm entities are the cause before going higher.

The pack plays best with a small group of friends sharing one outbreak. Each extra player keeps more of the map loaded and pulls more zombies toward the noise they make, so load scales with how spread out your group is. A group that sticks together in one area costs far less than the same group split across the whole map.

Take a backup of the world before any change. Builds of this pack are tied to its map, and the current 2.1 release is labelled for a new map only, so installing it over an older save can leave the world and the pack out of step. The safe path is to finish your current run on its build, then start fresh on 2.1.

You can, as long as every addition is a Forge mod built for 1.12.2 and is installed on both the server and every client. Removing a mod whose blocks or items were placed in the custom map can leave gaps or missing items in the world, so test changes on a copy of the save and keep your original backup until you are sure.

Mustard Virus is deliberately small: 34 mods, a fixed map and slow zombies, so the challenge is surviving in one place rather than climbing a long tech or magic progression. Larger zombie packs tend to stack hundreds of mods on random worlds with heavier memory needs. If your group wants a focused outbreak story on modest hardware, this is the lighter pick.

The pack is built around slow zombies, which changes how fights play out. A single one is easy to outpace, but several together can corner you in a building or block a road you need. That makes planning routes, light and exits matter more than raw weapon strength, and it rewards groups that move carefully and watch each other's backs.