Smooth SimplySwords SpellPower Compat

A small compatibility addon for Simply Swords and Spell Power on Minecraft 1.20.1 Fabric.

Simply Swords 1.70.2 still expects an older Spell Power API where spell schools exposed their backing attribute through SpellSchool.attribute.

Spell Power 1.6.x changed that API.

The result?

Open your inventory, let Minecraft calculate a Simply Swords weapon tooltip, and suddenly:

java.lang.NoSuchFieldError:
net.spell_power.api.SpellSchool.attribute

Not ideal.

Smooth SimplySwords SpellPower Compat bridges that API difference so you can keep using Simply Swords together with the newer Spell Power 1.6.x stack.

What This Mod Fixes

This addon patches the Simply Swords → Spell Power compatibility layer for Minecraft 1.20.1.

It updates the old attribute access used by Simply Swords to the newer Spell Power API.

In practice, this fixes crashes triggered when Minecraft tries to calculate or display Spell Power-related weapon attributes, including the common crash when opening the inventory.

The compatibility layer also handles the spell-school display path used by Simply Swords tooltips.

What Stays Working

The goal is not to disable Simply Swords' Spell Power integration.

It is to keep it working.

Simply Swords weapons can continue using their configured spell schools, including schools such as:

• Arcane
• Fire
• Frost
• Healing
• Lightning
• Soul

Weapon spell-power scaling remains handled by the existing Simply Swords and Spell Power systems.

This addon only replaces the outdated API bridge between them.

Requirements

Designed for:

Minecraft 1.20.1
Fabric

Required mods:

• Simply Swords 1.70.2
• Spell Power 1.6.x
• Fabric Loader

Install this addon alongside Simply Swords and Spell Power.

It does not require Smooth Classes.

Despite the name, this is a standalone compatibility patch and can be used in any Fabric 1.20.1 modpack using the affected versions.

Why Does This Exist?

Simply Swords 1.70.2 accesses the old Spell Power spell-school attribute field directly.

Older API:

school.attribute

The newer Spell Power API exposes the registered attribute through:

school.getAttributeEntry()

This addon patches the affected Simply Swords compatibility methods and resolves the attribute through the newer API instead.

In other words:

Simply Swords 1.70.2
        ↓
expects older Spell Power API
        ↓
Smooth SimplySwords SpellPower Compat
        ↓
Spell Power 1.6.x API

Tiny bridge.

One less crash.

Everyone goes home happy.

What Is Patched?

The addon targets the affected Fabric compatibility code used by Simply Swords for Spell Power integration.

The main compatibility paths covered are:

Spell Power Weapon Attributes

Fixes the attribute lookup used when Simply Swords applies Spell Power modifiers to weapons.

This is the code path responsible for the inventory crash caused by the removed SpellSchool.attribute field.

Spell School Display

Updates the spell-school attribute lookup used for Simply Swords spell-school display and tooltip information.

This prevents the same old API access from appearing again through another UI path.

Compatibility Scope

The initial release is intentionally narrow.

It is made for the affected Minecraft 1.20.1 stack:

Simply Swords 1.70.2
Spell Power 1.6.x
Fabric
Minecraft 1.20.1

This addon does not attempt to rewrite Simply Swords, replace Spell Power, or modify weapon balance.

If Simply Swords receives an official 1.20.1 update that already supports the newer Spell Power API, this compatibility addon may no longer be necessary.

Modpack Use

Yes, you may include this addon in modpacks.

It was created specifically to keep a modernized 1.20.1 RPG stack working without downgrading Spell Power or removing Simply Swords.

For dependency handling, make sure players also receive the required Simply Swords and Spell Power versions.

Smooth Ecosystem

This compatibility addon was originally created while maintaining the RPG stack used alongside projects such as:

Smooth Classes — classes, skill trees, abilities, summons and mounts
Smooth Progression — levels, XP and world progression
Smooth Odyssey — the modpack where compatibility problems come to become side projects

Smooth Classes is not a required dependency for this addon.

Bug Reports

If you still encounter a Simply Swords / Spell Power related crash, include:

• Minecraft version
• Fabric Loader version
• Simply Swords version
• Spell Power version
• This compatibility addon version
• latest.log
• Crash report, if one was generated

Please include the full stack trace when possible.

If the crash mentions another old Spell Power field or method, that usually means there is another compatibility path that needs patching.

Version

Smooth SimplySwords SpellPower Compat 1.0.0

Initial compatibility release for Simply Swords 1.70.2 and Spell Power 1.6.x on Minecraft 1.20.1 Fabric.