Psi

Psi

Psi is a mod about spell programming, inspired by Mahouka

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88.0K Downloads
fabricforgeneoforgeequipmentmagictechnology
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About this Mod



About

Warning: Psi Requires Patchouli for 1.16.5 and more recent versions. Older versions require AutoRegLib

Psi is a magical tech spell programming mod inspired by Mahouka Kokou no Rettousei. Don't worry if that doesn't make any sense.

The core of Psi is a system where you can create action sequences ("Spells") to be executed in the world. This system is followed by a leveling system containing ingame documentation and tutorials of the various concepts and pieces you'll get. The mod makes use of basic mathematical concepts, such as Vectors in its systems, which allows for great flexibility on what spells can do.

Psi spells can be shared and copied to and from outside sources, using ingame sharing tools. The main repository for user made psi spells is the Psi Spell Compendium on reddit.

Psi...

  • Is very flexible on what it allows you to do;
  • Encourages creativity and problem solving;
  • Ties in the reward to the creation process;
  • Can do some pretty cool stuff.

Learn more about Psi today

Visit the Official Website





Available Versions

Psi 1.21.1-110 (NeoForge)release
MC 1.21.1neoforge
September 1, 2026
Psi 1.21.1-110 (Fabric)release
MC 1.21.1fabric
September 1, 2026
1.21.1-108release
MC 1.21.1neoforge
February 22, 2026
1.21.1-107release
MC 1.21.1neoforge
December 7, 2025
1.21.1-105release
MC 1.21.1neoforge
July 26, 2025

How to Install Psi on Your Server

1

Order Server

Order a Minecraft Java server with at least 3 GB RAM (4 GB recommended).

2

Set fabric Loader

In the panel under "Egg", select the fabric loader and matching Minecraft version (1.21.1).

3

Install Mod

Open the mod browser in the dashboard and search for "Psi". Click "Install" – done! Alternatively, upload the .jar via SFTP to the /mods folder.

Compatibility

Mod Loaders

fabricforgeneoforge

Minecraft Versions

1.21.1, 1.20.1, 1.19.4 (+5 more)

Server-side

✓ Required

Recommended RAM

4 GB(min. 3 GB)

Frequently Asked Questions

Psi server crashes on startup – what to do?

Most common cause: wrong fabric version or insufficient RAM. Check the server log (latest.log) for "OutOfMemoryError" or "Mixin" errors. With Mado Hosting: ensure at least 3 GB RAM is allocated and the loader matches the mod version (1.21.1). You can switch loaders with one click in the panel.

Is Psi compatible with fabric and forge and neoforge?

Psi officially supports fabric, forge, neoforge for Minecraft 1.21.1, 1.20.1, 1.19.4. Note: Forge and Fabric mods are NOT cross-compatible – pick one loader and stick with it. The Mado dashboard automatically detects incompatible loader combinations.

Server lagging with Psi – how to optimize performance?

Recommended RAM: 4 GB (per 8 players). Use /spark profiler to check if Psi consumes the most tick time. Common fixes: reduce server view-distance to 8-10, install "performant" or "starlight" as supplementary mods on Forge. With Mado Hosting, your server runs on NVMe SSDs with dedicated CPU cores for minimal latency.

Rent Modded Server

Install Psi with just one click on your server.

Recommended RAM
4 GBfrom €5.2/mo
Minimum 3 GB | per 8 players
Create Server Now
1-Click Mod Install
NVMe SSD Storage
DDoS Protection included

Details

License
LicenseRef-Psi-License
Server-side
Required

Supported Versions

1.21.11.20.11.19.41.19.31.19.21.18.21.16.51.12.2