Iron's Spellbooks Tweaks in FTB Skies 2

Iron's Spellbooks Tweaks is a small config add-on for Iron's Spells 'n Spellbooks. Iron's itself only exposes a handful of options, so this mod adds extra TOML settings for things like mana, cooldowns, spell power and buff durations. It also covers restrictions such as blocked casting dimensions, a spell rarity cap and an inscription blacklist. The pack includes version 1.5.0.^[1][2]

Who it is for

It is mainly a tool for pack makers and server admins. You drop in the jar, edit one server-side file, and clients don't need a matching config. If you just play the pack, the main effect is that magic can be balanced or gated differently from plain Iron's Spellbooks. The sources don't tell me which values this pack actually sets, so check the config file in your own install before assuming any numbers.^[1][2]

What you can tune

• Mana, with bonuses to regen and max mana, or regen switched off entirely.^[1]
• Spell timing, through cooldown reduction and cast time reduction bonuses.^[1]
• Spell power and buff duration multipliers, each in a range of 0.0 to 10.0. Vanilla potions, food effects and beacon effects are not touched by the buff duration scaling.^[1]
• Restrictions: dimensions where casting is blocked, a cap on the highest rarity players can cast, and spells that cannot be inscribed.^[1]
• Black hole pull resistance per entity type, from 0.0 to 1.0, plus HP and damage scaling for several summoned creatures.^[1]

Per-world overrides and unlocks

Since version 1.5, a copy of the global config placed in a world's serverconfig folder overrides it for that world, and any missing keys fall back to the global file. Pack makers can also use datapack unlocks to gate spells, dimensions and bonuses behind advancements or boss kills. Players can run /isstweaks requirements to see what a spell or rarity tier needs.^[1][2]

Unverified I could not confirm from the sources where this mod fits in the pack's progression. It is not on the ATM Star path and no quests involve it, so there is no guided route for it.

Good news: there's nothing to craft to get going with this one. Iron's Spellbooks Tweaks is a config addon for Iron's Spells 'n Spellbooks. Its project page describes TOML options for mana, cooldowns, spell power and buff durations, plus dimension blocks, rarity gating, inscriptions and black hole resistance. So your first steps are about knowing what the addon can change, not about making items.^[1]

Unverified The sources here show no quests in this pack that involve this mod and no recipes that produce its items, so there is no recipe or quest to point you to.

What to know first

• The addon fills gaps in Iron's own settings. It doesn't touch Iron's serverconfig, which the project page says has known multiplayer sync bugs, and it applies its settings through attribute modifiers and hooks on Iron's public events.^[1]
• Its options are grouped into mana, spell timing, spell scaling, restrictions, black hole resistance and summon scaling. Summon scaling covers the HP and damage of summoned vexes, polar bears, Raise Dead undead and more.^[1]
• Multipliers stack multiplicatively with any HP or damage scaling other mods apply.^[1]

Changing settings for one world

The project page says that from version 1.5 on, the global config is the source of truth. To customize a single world, you drop a copy of the global file into that world's serverconfig folder and edit that copy. Any keys you leave out fall back to the global file.^[1]

The op-only /isstweaks copyconfig command copies the global config into the current world's serverconfig folder, so you can set up overrides in-game. It won't overwrite a per-world file that already exists.^[1]

For pack makers

The project page also describes a datapack-driven unlock system. Pack devs can gate spells, dimensions and bonuses behind advancements or boss kills, using JSON files that support advancement and entity_kill triggers.^[1]

This mod has no machines, multiblocks, power, fluids or item automation. It is a config-only addon for Iron's Spells 'n Spellbooks that adds server-side options Iron's doesn't expose. So the core mechanics here are about which values get adjusted and how they stack.^[1]

How the tweaks are applied

The mod reads its own file and leaves Iron's serverconfig alone. It applies your settings through attribute modifiers and hooks on Iron's public events. All options are server-side, so clients don't need a matching config.^[1]

The pack ships every option at the mod default or in its disabled state. Nothing changes from base Iron's behavior until someone edits the file.^[3]

Mana

mana.startingMaxMana adds a flat bonus to the player's max mana attribute on every login. Iron's default is 100, so a value of 400 would give 500 total. The pack leaves it at -1, which disables it.^[3]

mana.baseManaRegenPercent works the same way for the mana regen attribute, also applied on login as a flat addition. Iron's default is around 1.0, so a value of 4.0 would give an effective rate of 5.0. The pack leaves it at -1, which disables it.^[3]

mana.disableManaRegen switches off passive mana regen entirely. It is done as a tick drainback because Iron's regen path doesn't fire a cancellable event. The pack has it set to false.^[3]

Cooldowns and cast time

cooldown.cooldownReductionBonus and cooldown.castTimeReductionBonus are additive bonuses to every player's cooldown reduction and cast time reduction attributes. Both accept -10.0 to 10.0 and stack with gear and effects. Around 0.5 roughly halves cooldowns or cast times, and negative values lengthen them. The pack sets both to 0.^[3]

Spell power and buff durations

spells.spellPowerMultiplier multiplies every player's spell power attribute and stacks multiplicatively with gear and other modifiers. The range is 0.0 to 10.0, and the pack uses 1, which changes nothing. Damage tooltips reflect the scaled value.^[1][3]

spells.buffDurationMultiplier scales the duration of buff and debuff effects from Iron's spells. It does not touch vanilla potions, food effects, beacon effects or effects from other mods. The pack value is 1. The active effect countdown in your inventory shows the real time, while the spell tooltip shows the unmodified base.^[1][3]

Which effects count is decided by spells.buffDurationNamespaces. The pack lists irons_spellbooks, cataclysm_spellbooks, dacxirons, gametechbcs_spellbooks, gtbcs_geomancy_plus, hazennstuff, ias_spellbooks and traveloptics. You can add addon namespaces or remove entries. Vanilla minecraft is intentionally unsupported and ignored if listed.^[3]

Restrictions

• restrictions.spellCastingDisabledDimensions fully blocks spell casting in the listed dimensions. It affects players only, not mob casters. The pack list is empty, so casting is allowed everywhere.^[3]
• restrictions.maxSpellRarity caps the highest rarity players can cast: common, uncommon, rare, epic or legendary. Setting 'uncommon' allows common and uncommon but blocks the rest. Mob casters are unaffected. The pack leaves it empty, which disables the cap.^[3]
• restrictions.inscriptionBlacklist lists spell IDs that can't be inscribed at the inscription table, written like irons_spellbooks:fireball. A blocked inscription is cancelled silently. The pack list is empty.^[3]

Black hole resistance

Iron's hardcodes a 0.3 minimum black hole pull regardless of the knockback resistance attribute. blackhole.blackholeImmunity lets you push past that floor for specific entity types, mainly bosses. Entries look like entity_id:strength, where 0.0 means no effect and 1.0 means fully immune. It affects the black hole only, not other movement spells or vanilla knockback. The pack list is empty.^[3]

Summon scaling

The summon multipliers each accept 0.0 to 10.0 and are all set to 1 in the pack. They stack multiplicatively with any HP or damage scaling from other mods.^[1][3]

• Vex: summons.summonVexHpMultiplier and summons.summonVexDamageMultiplier.^[3]
• Raise Dead skeletons and zombies: summons.raiseDeadHpMultiplier and summons.raiseDeadDamageMultiplier.^[3]
• Polar bear: summons.summonPolarBearHpMultiplier and summons.summonPolarBearDamageMultiplier. Iron's already scales bear base HP with spell level and spell power before the multiplier applies.^[3]
• Horse: summons.summonHorseHpMultiplier only. Iron's already scales horse base HP with spell power first.^[3]
• Summon Swords: summons.summonSwordsDamageMultiplier for damage per hit.^[3]

Unverified The mod's project page also describes per-world config overrides, a datapack-driven unlock system for per-player bonuses and rarity or dimension exemptions, and /isstweaks commands. The pack files provided here don't show whether this pack's version includes those features or uses any unlocks, so treat them as unconfirmed for this pack.

This addon has its own file, config/irons_spellbooks_tweaks-server.toml, so none of this lives in Iron's own server config. Every option the pack's file compares against the mod default sits at that default, so this pack doesn't change any of them. Here is where each group stands, so you know what you can tweak.^[1][3]

Mana

• mana.startingMaxMana is -1 in the pack, which means disabled. If you set it, the value is added to max mana on every login. Iron's default is 100, so 400 would give you 500 total.^[3]
• mana.baseManaRegenPercent is also -1 (disabled). If you set it, it is added flat to your mana regen. Iron's default is around 1.0, so 4.0 would give an effective 5.0.^[3]
• mana.disableManaRegen is false, so passive mana regen works normally.^[3]

Cooldowns and cast time

cooldown.cooldownReductionBonus and cooldown.castTimeReductionBonus are both 0 in the pack, the same as the mod default. They accept values from -10.0 to 10.0 and stack with gear and effects. Around 0.5 cuts cooldowns roughly in half, or makes spells cast roughly twice as fast. Negative values make both longer.^[3]

Spell power and buff duration

• spells.spellPowerMultiplier is 1, so spell power is unchanged. The range is 0.0 to 10.0, and it stacks multiplicatively with gear and other modifiers.^[3]
• spells.buffDurationMultiplier is 1, so buff and debuff durations are unchanged. It never touches vanilla potions, food effects or beacon effects.^[1][3]
• spells.buffDurationNamespaces decides which mods' effects get scaled. The pack lists irons_spellbooks, cataclysm_spellbooks, dacxirons, gametechbcs_spellbooks, gtbcs_geomancy_plus, hazennstuff, ias_spellbooks and traveloptics. The vanilla minecraft namespace is ignored if you add it.^[3]

Restrictions

The pack doesn't restrict anything. restrictions.maxSpellRarity is empty, so every rarity is allowed. restrictions.spellCastingDisabledDimensions and restrictions.inscriptionBlacklist are empty lists, so you can cast in every dimension and inscribe every spell. These options only affect players, and the rarity limit doesn't affect mob casters either.^[3]

Summons and black hole

Every summon multiplier is 1 in the pack, so summons behave as in the mod's defaults. That covers summons.raiseDeadDamageMultiplier, summons.raiseDeadHpMultiplier, summons.summonHorseHpMultiplier, summons.summonPolarBearDamageMultiplier, summons.summonPolarBearHpMultiplier, summons.summonSwordsDamageMultiplier, summons.summonVexDamageMultiplier and summons.summonVexHpMultiplier. Each accepts 0.0 to 10.0, and a damage multiplier of 0.0 reduces every hit to zero.^[3]

blackhole.blackholeImmunity is an empty list in the pack, so no entity gets extra resistance to black hole pull. Entries use the format entity_id:strength, from 0.0 (no effect) to 1.0 (fully immune).^[3]

Unverified The file doesn't state a mod default for the black hole immunity list, the restriction options or the buff duration namespace list, so whether the pack changed any of them is unverified.

FTB Skies 2 1.22.0 ships Iron's Spellbooks Tweaks 1.5.0. The mod was first included in the pack in 1.18.1 or earlier, so it's been around for a while.^[2]

Version 1.5.0

This is the release you're playing with in 1.22.0, and it adds a few handy features. The values below are the mod's own defaults from its changelog. The sources don't show whether the pack changes any of them.^[2][4]

• Per-world config overrides: drop a copy of the global config into a world's serverconfig/ folder to override settings for that world only. Any missing keys fall back to the global config.^[4]
• /isstweaks copyconfig is an op-only command that copies the global config into the current world's serverconfig/ folder. It won't overwrite a per-world file that already exists.^[4]
• spellPowerMultiplier is a new option in the [spells] section. It ranges from 0.0 to 10.0 and defaults to 1.0. It scales the SPELL_POWER attribute on every player, and spell damage tooltips show the scaled value.^[4]
• buffDurationMultiplier is also in [spells], with a range of 0.0 to 10.0 and a default of 1.0. It scales buff and debuff durations from Iron's Spellbooks and its addons. Vanilla potions, food effects and beacon effects are not touched.^[4]
• buffDurationNamespaces, in [spells], lists which mods get their effects scaled. The defaults cover Iron's Spellbooks plus Cataclysm Spellbooks, dacxirons, GameTechBC's Spellbooks, GTBC's Geomancy Plus, Hazen 'n Stuff, Illage and Spell-age, and Traveloptics. Effects from unlisted non-vanilla namespaces get logged once per session for visibility.^[4]

Unverified No pack changelog entries for this mod were available, and changelogs for mod versions before 1.5.0 weren't provided. What changed between the version first added to the pack and 1.5.0 is unverified.