Jeff's ISS Addons

Jeff's ISS Addons

An Iron's Spells 'n Spellbooks Addon.

by
494 Downloads
neoforgeadventureequipmentmagic
Rent Server with this Mod

Screenshots

Blackhole sucking in blocks with a spin
Telekinesis target stops moving to cursor
Flying with telekinesis
Telekinesis now abides by Newton's third law
Telekinesis on a projectile
Uno reverse on a necromancer

About this Mod

An Iron's Spells 'n Spellbooks addon. Focused on incorporating items in minecraft with Iron's Spells 'n Spellbooks and other modifications to existing spells or features.

Recipes:

  • Arcane Essence: Lapis lazuli + Amethyst shard
  • Cinder Essence: Arcane essence + Blaze rod + Obsidian + Ghast tear
  • Common Ink: Arcane Essence + Black Dye + Glass Bottle

Scrolls:

  • Scrolls no longer disappear upon using, scrolls will instead deal damage to the caster.
    (Common = 1 Hearts, Uncommon = 1.5 Hearts ..., Legendary = 3 Hearts)
  • Damage scales based off the cooldown of the spell
  • Optionally consumes mana
  • Feature can be disabled for certain spells only

Telekinesis:

  • Telekinesis now works on projectiles and will set the source of damage to the caster.
  • Middle clicking with telekinesis will stop your target from following your cursor.
  • Left clicking with telekinesis will throw your target in the direction of your cursor.
  • Scrollwheel up with telekinesis will increase the distance of your target from you.
  • Scrollwheel down with telekinesis will decrease the distance of your target from you.

Counterspell:

  • Counterspell now deflects projectiles. [Can be configured to only deflect magical projectiles]

Gust:

  • Gust now deflects entities such as projectiles & falling blocks.

Black hole:

  • Black holes now have a spin and will pull in entities in a orbiting pattern.
  • Configuration options on what blocks the blackhole can absorb
  • Option for black holes to be telekinesis-able (by default, it is telekinesis-able)
  • Entities in the black hole's area of effect will move when the black hole moves.
  • Black hole disappears faster, the more blocks it sucks up.
  • Black holes now only deals damage when an entity touches the center.
  • Black hole's duration can be extended by casting spells into it's core. (the duration increase scales with damage of the spell)

Everything is configurable!

it's either in jeffissaddons-server.toml or jeffissaddons-startup.toml.

Below are the planned features for this mod (ordered).

Blackhole:

  • Can craft certain recipes using blackhole's gravity

[New spell] Blood Engine:

  • This spell applies the "Blood Mana Conversion" effect.
  • While under the effect, everytime the caster runs out of mana, the caster's hp will be used instead of mana.
  • While under the effect, healing is disabled.
  • The hp reduction bypasses all effects / armor.

Telekinesis:

  • now works on blocks (imagine magical grappling hook)

[New spell] [Name to be decided]:

  • A variant of ray of frost with increased damage, range, & pierce
  • But the damage goes down the more you move (in direction / position)
  • Meant to be good against static entities.

Available Versions

Jeff's ISS Addons 1.6.0release
MC 1.21.1neoforge
December 15, 2025
Jeff's ISS Addons 1.5.0release
MC 1.21.1neoforge
December 8, 2025
Jeff's ISS Addons 1.4.0release
MC 1.21.1neoforge
November 28, 2025
Jeff's ISS Addons 1.3.0release
MC 1.21.1neoforge
November 27, 2025
Jeff's ISS Addons 1.2.0release
MC 1.21.1neoforge
November 25, 2025

How to Install Jeff's ISS Addons on Your Server

1

Order Server

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

2

Set neoforge Loader

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

3

Install Mod

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

Compatibility

Mod Loaders

neoforge

Minecraft Versions

1.21.1

Server-side

Required

Recommended RAM

4 GB(min. 3 GB)

Frequently Asked Questions

Jeff's ISS Addons server crashes on startup – what to do?

Most common cause: wrong neoforge 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 Jeff's ISS Addons compatible with neoforge?

Jeff's ISS Addons officially supports neoforge for Minecraft 1.21.1. The Mado dashboard automatically detects incompatible loader combinations.

Server lagging with Jeff's ISS Addons – how to optimize performance?

Recommended RAM: 4 GB (per 8 players). Use /spark profiler to check if Jeff's ISS Addons 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 Jeff's ISS Addons with just one click on your server.

Recommended RAM
4 GBab €8/mo
Min. 3 GB | +1 GB pro 8 Spieler
Create Server Now
1-Click Mod Install
NVMe SSD Storage
DDoS Protection included

Details

License
LicenseRef-All-Rights-Reserved
Server-side
Required

Supported Versions

1.21.1