// modpack server guide
Cobblemon Expanded server hosting & setup guide
A Cobblemon Expanded server needs Java 21 and about 4.5–6.5 GB of RAM for up to 15 players.
Cobblemon with missing features added in! Pokémon Towns, rideable Pokémon, Mega Evolutions, Gym Leaders, Pokémon plushies, and more!
Summary from Cobblemon Expanded (by Jonathan) on Modrinth.
Cobblemon Expanded (by Jonathan) is a Fabric modpack for Minecraft 1.21.1 (older versions go back to 1.20.1) with 99 mods. We'd pick our Premium plan (8 GB) for it.
Quick facts
| Loader | Fabric |
|---|---|
| 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 | 99 modsCounted from the pack's file list on Modrinth. None are marked client-only. |
| RAM | About 3–3.5 GB for 1–3 playersBy player count. |
| Downloads | 303,983 on Modrinth |
| Last updated | June 18, 2025 (version 1.1.8-hotfix) |
| First published | October 12, 2024 on Modrinth |
| Server support | Required: the pack has mods that must run on the server. |
| Server pack | Server Pack - Cobblemon Expanded (by Jonathan) 1.1.8.zipPublished by the pack's authors with the latest version on Modrinth. |
| Modrinth tags | adventure, lightweight |
Cobblemon Expanded server files
Yes. The authors publish a server pack with Cobblemon Expanded's latest version on Modrinth: Server Pack - Cobblemon Expanded (by Jonathan) 1.1.8.zip (version 1.1.8-hotfix). It's the server's side of the pack, ready to unzip.
How much RAM does a Cobblemon Expanded server need?
| Players online | RAM | DSN plan |
|---|---|---|
| 1–3 players | About 3–3.5 GB | Standard (4 GB) |
| 4–8 players | About 3.5–5 GB | Premium (8 GB)Standard (4 GB) can do if players stay close. |
| 9–15 players | About 4.5–6.5 GB | Premium (8 GB) |
Estimated from 99 mods on the server with our RAM calculator, not measured: low end if players stay together, high end if they spread out.
By this estimate Standard (4 GB) can run a small group. Our pick below, Premium, leaves room for more players and for the pack growing with updates.
Set Java's heap (-Xmx) 10–15% under the RAM you have, about -Xmx7000M on 8 GB. Fabric 1.21.1 takes it in the java command (-Xmx), usually in the start script. RAM guide.
Cobblemon Expanded server requirements
| Java | Java 21 |
|---|---|
| Loader | Fabric for Minecraft 1.21.1 |
| CPU | Fast single-core speed (one main thread). |
| RAM | About 3–6.5 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 Cobblemon Expanded
Premium
8 GB RAM · planned launch price $30/month
At about 99 Fabric mods this is a mid-size pack, and 8 GB gives it room for the mods plus the chunks your players load.
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 Premium servers open.
More than 15 players, or lots exploring at once? Go up to Heavy (12 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 Cobblemon Expanded server on your own PC
What's specific to Cobblemon Expanded, 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.
Download
Server Pack - Cobblemon Expanded (by Jonathan) 1.1.8.zipfrom the pack's latest version on Modrinth and unzip it into an empty folder. Follow its readme if it has one. - Start it and accept the EULA.
Run the start script in the server files, or
java -jaron the Fabric 1.21.1 server launcher, 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 Cobblemon Expanded on DSN
Once we relaunch (join the launch list), on DSN you'd install Cobblemon Expanded from the panel's Modrinth modpack installer (version 1.1.8-hotfix), pick Java 21 on the Startup tab and accept the EULA in the console. No port forwarding.
How to play Cobblemon Expanded with friends
Each player installs Cobblemon Expanded version 1.1.8-hotfix with the Modrinth App or Prism Launcher, the same version as the server, and adds the server's address under Multiplayer.
Different versions of Cobblemon Expanded 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 Cobblemon Expanded
Can't keep up! Is the server overloaded? means ticks take longer than 50 ms; more RAM won't fix that once Cobblemon Expanded has enough (tick lag guide). For Cobblemon Expanded:
- 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.
Common Cobblemon Expanded crashes
What a Fabric 1.21.1 server running Cobblemon Expanded hits most. For any other error, paste the log into the free crash log analyzer.
- Wrong Java version. Cobblemon Expanded 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. Cobblemon Expanded (99 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. The Cobblemon Expanded pack file marks none of its mods client-only, so this usually means one was copied over from a player's mods folder. 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 Cobblemon Expanded 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 Cobblemon Expanded past version 1.1.8-hotfix, back up the world: see updating a modpack server without losing your world.
Bugs in Cobblemon Expanded itself go to its authors through its Modrinth page. Server problems on DSN: hello@dsnservers.com or Discord.
Packs like Cobblemon Expanded
More: Cobblemon server hosting, all modpack guides and how to make a modded server.
Run Cobblemon Expanded on DSN when we relaunch.
Our pick, Premium: 8 GB, planned at $30/month.
DSN Servers isn't affiliated with Cobblemon Expanded (by Jonathan) or Modrinth. The pack's name, icon, summary and stats come from Modrinth's public API (checked October 4, 2026).