// modpack server guide
Create Ultimate server hosting & setup guide
A Create Ultimate server needs Java 21 and about 3–3.5 GB of RAM for up to 3 players.
All addons you need for Create
Summary from Create Ultimate on Modrinth.
Create Ultimate is a NeoForge and Forge modpack for Minecraft 1.21.1 (older versions go back to 1.20.1) with 80 mods, 79 of which run on the server. We'd pick our Standard plan (4 GB) for it.
Quick facts
| Loader | NeoForge and Forge |
|---|---|
| Minecraft versions | 1.21.1, 1.20.1 |
| Java needed | Java 21 for Minecraft 1.21.1Older pack versions: Java 17 for 1.20.1. Java version chart. |
| Mods | 79 run on the server80 in the pack. The other one is client-only, and the server skips it. |
| RAM | About 3–3.5 GB for 1–3 playersBy player count. |
| Downloads | 129,659 on Modrinth |
| Last updated | September 17, 2026 (version 2.0.3) |
| First published | April 17, 2024 on Modrinth |
| Server support | Required: the pack has mods that must run on the server. |
| Server pack | Not published separatelyHow to build the server. |
| Modrinth tags | technology, kitchen-sink |
Create Ultimate server files
No. Create Ultimate has no separate server pack on Modrinth, so the server is built from the .mrpack: the NeoForge or Forge server for Minecraft 1.21.1, plus the pack's overrides folder and the server-side mods its modrinth.index.json lists. A modpack installer does this for you; our guide shows how to make a server for a modpack with no server pack.
How much RAM does a Create Ultimate server need?
| Players online | RAM | DSN plan |
|---|---|---|
| 1–3 players | About 3–3.5 GB | Standard (4 GB) |
| 4–8 players | About 3.5–4.5 GB | Premium (8 GB)Standard (4 GB) can do if players stay close. |
| 9–15 players | About 4–6 GB | Premium (8 GB)Standard (4 GB) can do if players stay close. |
Estimated from 79 mods on the server with our RAM calculator, not measured: low end if players stay together, high end if they spread out.
Set Java's heap (-Xmx) 10–15% under the RAM you have, about -Xmx3500M on 4 GB. NeoForge or Forge 1.21.1 reads it from user_jvm_args.txt: uncomment the -Xmx line. RAM guide.
Create Ultimate server requirements
| Java | Java 21 |
|---|---|
| Loader | NeoForge or Forge for Minecraft 1.21.1 |
| CPU | Fast single-core speed (one main thread). |
| RAM | About 3–6 GB for 1–15 players (table above) |
| Disk | The server files, a growing world and backups |
| Network | TCP port 25565 open to players |
Recommended plan
Our pick for Create Ultimate
Standard
4 GB RAM · planned launch price $16/month
At about 79 mods this is a light pack, so 4 GB of RAM covers it for a small group.
Ordering is closed until we relaunch. We aren't taking orders or payments while we move to new hardware. Join the launch list and we'll email you when Standard servers open.
More than 3 players, or lots exploring at once? Go up to Premium (8 GB). Not sure? Email hello@dsnservers.com.
Planned launch price in USD, billed monthly once ordering opens, with a 7-day refund window.
How to make a Create Ultimate server on your own PC
What's specific to Create Ultimate, step by step. The full walkthrough for any pack: how to make a modded Minecraft server.
- Install Java 21.
Check with
java -version. Java version chart. - Get the server files.
Build them from the .mrpack, as in server files above.
- Start it and accept the EULA.
Run the start script in the server files, or the
run.sh/run.batthe NeoForge or Forge 1.21.1 installer writes, then seteula=trueineula.txtif you accept Mojang's EULA (EULA step). - Set the RAM with
-Xmx, sized from the table above. - Let friends connect: forward TCP 25565, or use a tunnel or host behind CGNAT (can't connect?).
Or run Create Ultimate on DSN
Once we relaunch (join the launch list), on DSN you'd install Create Ultimate from the panel's Modrinth modpack installer (version 2.0.3), pick Java 21 on the Startup tab and accept the EULA in the console. No port forwarding.
How to play Create Ultimate with friends
Each player installs Create Ultimate version 2.0.3 with the Modrinth App or Prism Launcher, the same version as the server, and adds the server's address under Multiplayer.
Different versions of Create Ultimate on the server and a client show up as Mismatched mod channel list or mod rejections. Why friends can't join, timeouts included.
Lag and performance on Create Ultimate
Can't keep up! Is the server overloaded? means ticks take longer than 50 ms; more RAM won't fix that once Create Ultimate has enough (tick lag guide). For Create Ultimate:
- Measure first: spark's
/spark tpsand profiler work on 1.21.1 and name the mod or machine using the tick time. - Distances:
view-distance=8and a lowersimulation-distanceinserver.properties. - Pre-generate: Chunky for 1.21.1,
/chunky radius 3000then/chunky start, before people explore. - Create contraptions and train networks tick in every loaded chunk; check them first when TPS drops.
Common Create Ultimate crashes
What a NeoForge and Forge 1.21.1 server running Create Ultimate hits most. For any other error, paste the log into the free crash log analyzer.
- Wrong Java version. Create Ultimate on Minecraft 1.21.1 needs Java 21. Started on Java 17, it stops with
UnsupportedClassVersionError: ... class file version 65.0, this version of the Java Runtime only recognizes class file versions up to 61.0. Java version fix. - Out of memory. Create Ultimate (79 mods on the server) needs about 3–3.5 GB for 1–3 players;
java.lang.OutOfMemoryErrormeans it ran out. Out-of-memory fix. - Client-only mod on the server. Create Ultimate includes 1 client-only mod, which a server install skips; copying a player's mods folder brings it back and stops the server. Check a mods list with the client-or-server-side checker. Client-only mod fix.
- After adding or updating a mod. Mods you add to Create Ultimate by hand usually crash it with a missing dependency or a mixin conflict.
- Ticking entity or block entity. The crash report names it and gives its coordinates. Ticking entity fix.
Updates and support
Before moving Create Ultimate past version 2.0.3, back up the world: see updating a modpack server without losing your world.
Bugs in Create Ultimate itself go to its authors through its Modrinth page. Server problems on DSN: hello@dsnservers.com or Discord.
Packs like Create Ultimate
More: NeoForge server hosting, all modpack guides and how to make a modded server.
Run Create Ultimate on DSN when we relaunch.
Our pick, Standard: 4 GB, planned at $16/month.
DSN Servers isn't affiliated with Create Ultimate or Modrinth. The pack's name, icon, summary and stats come from Modrinth's public API (checked October 4, 2026).