Create has become one of the most common reasons people come to us for a modded server, and more and more of those servers run it inside a heavy pack of around 300 mods. Create is a pleasure to play and a particular kind of job to host, because the things players build with it keep moving and keep working long after they walk away. This post covers what makes a Create server different, how to pick the version and loader, the config worth setting before launch, the rules that keep a Create SMP healthy over months, and how to profile and back it up properly.
It sits at the centre of a short series. The detailed lag work is in diagnosing and capping Create lag, and choosing addons and packs is in choosing a Create SMP setup.
What makes Create different to host
Most modded tech runs as machines that sit still: a block entity that does some work each tick. Create has plenty of those, but it adds three things that behave differently on a server.
Kinetic networks
Create machines run on rotation. A water wheel or steam engine turns a shaft, and that rotation travels through cogs, belts and gearboxes to everything connected. Each network has a stress budget, and every component draws from it. The cost to the server comes from the size of these networks and how often they change. Placing, breaking or reconfiguring part of a large network makes Create work out speeds and stress across it again, and some components check their power source on a timer as well. One small mill is cheap. Hundreds of components on one sprawling network that players keep editing is a different load.
Contraptions
A contraption is a group of blocks that Create lifts out of the world and moves as a single entity: a drill rig on a mechanical bearing, a piston-driven elevator, a harvester on a minecart. While it moves, the server has to track it, check collisions against the entities around it, and run the actors mounted on it (drills, harvesters, deployers) against the blocks they pass. Contraption collision is expensive enough that the Create team listed further optimisation of it in the 6.0.10 changelog. Big contraptions, and many of them running at once, are the usual source of a Create server's worst spikes.
Trains
Trains are contraptions too, with a twist. The Create wiki is clear that trains can travel through unloaded chunks without loading them, and a train that stops at a station in an unloaded chunk leaves that chunk unloaded. So base Create trains are not chunk loaders. The trouble comes when players add chunk loading on top, through an addon such as Create: Power Loader, which can sit on trains, contraptions and stations, or through a claims mod that force-loads chunks. A rail network with chunk loaders along it can keep a large area of the world ticking around the clock, with no player anywhere near.
Picking the version and loader
As of October 2026, Create's official releases cover two main targets:
- Minecraft 1.21.1 on NeoForge, where Create 6.0.10 (April 2026) is the newest official release.
- Minecraft 1.20.1 on Forge, where 6.0.8 is the newest official release. The 1.20.1 builds are also tagged for NeoForge on 1.20.1.
There is an official Fabric port for 1.20.1 as well, at 6.0.8.1, and community Fabric ports for newer Minecraft versions. We would not run a community port on a server people care about unless the pack you want depends on it.
In practice the pack decides. Most new Create packs target NeoForge 1.21.1. A lot of established ones, and a large share of the addon catalogue, still sit on Forge 1.20.1, which is why that version remains so common. The general trade-offs are in choosing a mod loader, and the setup steps are in modpack server setup.
Sizing, briefly
A 300-mod Create pack wants a fair amount of heap, but the thing that decides how many players and machines it can carry is single-thread CPU speed, because the main tick runs on one core. Extra RAM keeps it stable. It does not make contraptions cheaper. The ranges and the reasoning are in sizing a heavy modpack server and choosing a CPU for Minecraft.
Config worth setting before launch
Create's server config lives in the world folder at serverconfig/create-server.toml. Packs often ship a copy in defaultconfigs/, which is applied to new worlds, so edit that one before the first start if you want the settings to apply from day one. The keys below exist in both the 1.20.1 and 1.21.1 source, with the defaults the source sets.
maxBlocksMoved(default 2048) caps how many blocks a single contraption can contain. This is the most useful single cap on a public server.maxChassisRange(default 16) andmaxPistonPoles(default 64) limit how far a contraption's reach extends.maxBeltLength(default 20) caps belt length.maxRotationSpeed(default 256 RPM) caps how fast any kinetic block can spin.kineticValidationFrequency(default 60) is the number of ticks between kinetic blocks checking their power source is still valid.- In the trains section,
maxBogeyCount(default 20) caps bogeys per train andmaxAssemblyLength(default 128) caps a station's assembly track. In 6.0.10 these two gained hard upper limits of 200 and 512.
Lower the contraption and train caps for a public SMP rather than raising them, and change one thing at a time so you can see what each change did.
Server rules that keep a Create SMP healthy
Config sets hard limits. Rules cover what config cannot.
- Contraption size: publish a block limit for moving builds, matched to
maxBlocksMoved, and ask for large rigs to be cleared with staff. - Train count: limit active trains per player or team, and ask players to park trains they are not using.
- Chunk loader policy: decide whether chunk loaders are allowed at all, how many chunks each player gets, and whether trains may carry them. Write it down before launch, because taking chunk loaders away later causes more arguments than never handing them out.
- Off-switches: ask that farms and factories have a lever or clutch, so staff can stop one without breaking it.
The general shape of SMP rules is in running a Minecraft SMP.
Profiling with spark
When the server slows, measure before you guess. spark runs on Forge, NeoForge and Fabric. Run /spark profiler start --timeout 300 during a busy window, open the report, and use the sources view to see which mods the tick time goes to. If Create dominates, the call tree usually points at contraptions, a specific kind of block entity, or entity collision. /spark tickmonitor reports slow ticks as they happen, which helps when the lag comes in bursts. The full method, with what each culprit looks like, is in diagnosing and capping Create lag.
Back up before every big update
Large Create releases change mechanics and internals, and addons need to catch up with each one. Update Create before an addon supports the new version, or the other way round, and the server can refuse to start or load with missing blocks. Take a full backup before every pack or Create update, test the update on a copy of the world, and keep the backup until players have had a few days on the new version. The routine is in Minecraft server backups, and a pre-launch run-through for big packs is in the big modpack launch checklist.
Run a Create server with sensible caps, clear rules and a profiler on hand, and it holds up well, even inside a large pack. It does reward a fast core underneath, because contraptions and factories add a lot of work to every tick.