Project Ozone 2 at a glance
| Type | skyblock modpack with a very broad mod list and a quest book |
|---|---|
| Minecraft version | 1.7.10 |
| Mod loader | Forge - the modpack browser sets the matching version itself |
| Java | Java 8 - newer Java versions won't start Forge for 1.7.10 |
| Game modes | Normal, Titan and Kappa - Titan and Kappa make recipes much harder |
| Source | CurseForge - installable in the panel through the modpack browser |
| World size | small - progress happens on and around the island |
| Bottleneck | tick time from many machines, not memory |
| Recommended plan | plan M for two to three players, plan L for groups |
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Project Ozone 2 server hosting
Prepaid from €2.99 / month, unlimited slots, no minimum term. The right plan is listed in the RAM table below.
Plans & pricesWhat sets Project Ozone 2 apart from other skyblock packs
Project Ozone 2 is a skyblock pack with the scope of a big kitchen-sink pack. While lean skyblock packs ship a few dozen mods, this one brings hundreds - tech, magic, storage systems and automation. The way there leads through the quest book, which takes you step by step from the starting island to complex production chains.
On top of that there are three game modes. Normal is the entry point; Titan and Kappa make many recipes considerably more expensive and stretch the game over weeks. Agree on the mode as a group before your first session together - it applies to the whole world, and switching in the middle of a run scrambles the progress so far. How to set it is described on the pack page on CurseForge.
Java 8 and Minecraft 1.7.10 - what that means for the server
Project Ozone 2 only runs on Java 8. Forge for Minecraft 1.7.10 won't start on Java 17 or 21, and the server aborts while loading. You change the Java version in the web interface under Startup in the Docker image field, explained step by step in changing the Java version.
The old base has a second consequence: more memory only helps up to a point. Java 8 cleans up very large heaps more slowly, which shows up as short stutters. A mid-sized plan with a sensible view distance therefore often runs smoother than the largest plan with the maximum allocation.
Players need exactly the same pack version as the server. An update on the server side therefore always means updating all players too before they reconnect.
Why a small island still keeps the server busy
The load comes from machines, not terrain. Skyblock worlds take up very little storage, but later in the game dozens of generators, sieves and factories run side by side in a tight space. Every one of them is calculated in every tick - and because Minecraft simulates the world essentially on one CPU core, its performance decides whether you keep a smooth 20 TPS.
Typical causes of dropping TPS are items left lying around from full chains and machines that keep producing without anything taking their output. Consistently voiding overflows and running large setups only as fast as their consumers does more than a bigger plan. How to find the cause is shown in lag and TPS.
Which plan for Project Ozone 2?
The thresholds below apply to this pack - a light Vanilla+ pack and a kitchen-sink pack with a hundred running machines behave completely differently. You can upgrade at any time without losing data and only pay the difference.
| Group | Plan | RAM | Price | Why | Order |
|---|---|---|---|---|---|
| Solo or duo | Plan M | 4 GB | €5.99 / month | The usual size to start with - the island is small and the quest book is fresh. | Order M |
| 3-8 players | Plan L | 8 GB | €11.99 / month | Several islands with automation running all the time need headroom. | Order L |
| Larger groups | Plan L | 8 GB | €11.99 / month | Rarely more here - on Java 8 extra memory hardly pays off, the CPU is the bottleneck. | Order L |
| Storage | Plan M | 4 GB | €5.99 / month | Skyblock worlds stay small, there is plenty of room for your own backups. | Order M |
The memory is taken proportionally from the plan via -XX:MaxRAMPercentage - you don't need to maintain a fixed -Xmx. The basics are covered in the RAM guide.
Setting up Project Ozone 2 on the server
- Stop the server in the web interface. Setup and version changes only apply while the server is stopped.
- Search for "Project Ozone 2: Reloaded" in the modpack browser and install the version you want. The installer sets Minecraft 1.7.10 and Forge itself.
- Under Startup, select Java 8 in the Docker image field.
- Start the server. The first start takes several minutes because Forge registers all mods - don't cancel it.
- Wait for
Donein the console, then check in game that you are standing on the starting island in the void. - Players install exactly the same pack version and connect via IP and port.
Common pitfalls with Project Ozone 2
Server won't start, error right while loading
Cause: The server runs on Java 17 or 21. Forge for Minecraft 1.7.10 needs Java 8.
Fix: Switch to Java 8 under Startup and restart - see changing the Java version.
Normal landscape instead of a skyblock island
Cause: The world was created with settings that don't match the pack - for example after replacing server.properties with a default file.
Fix: Use the pack's world generation, delete the world folder and let it be created again. Chunks that already exist don't change afterwards.
"Mod rejections" when joining
Cause: Client and server run different pack versions.
Fix: Bring every player to exactly the server's version. Always update server and clients together.
TPS drop in the late game
Cause: Many setups running at once and items left lying in loaded chunks.
Fix: Void overflows, limit production rates, narrow down the cause in the console - see lag and TPS.