Magic

The rules that apply to every spell. What a particular spell does is on its own page - see Spells.

A spell's save DC

10 + the spell's level for the class casting it + your casting ability modifier + your Spell Focus feats.

The casting ability is the class's own: Intelligence for a Wizard, Charisma for a Sorcerer or Bard, Wisdom for a Cleric, Druid, Paladin or Ranger.

A few abilities set their own DC instead, and say so on their page. Eldritch Blast is one: its Dark Pact effects use 5 + (Warlock levels / 2) + Charisma modifier.

What staying in one class is worth

Four classes are paid for staying pure, and only for spells out of your own book - nothing below touches a scroll, a wand or an ability.

Pure means every level you have is in that class - 30 of them for a prestige class, since a prestige class cannot begin before level 11. Ten levels of God's Eye Scout are the one exception: exactly ten count as though they were levels of the class you are keeping pure.

A Pale Master has no spells of its own, but half its levels are added to your caster level - the number that decides how long a spell lasts and how many dice it rolls - for anything you cast as a Bard, Sorcerer, Wizard, Assassin or Warlock.

While you are in another shape

A spell you cast while polymorphed does not use the DC above, unless you cast it from an item or the spell is itself a shape change:

Your saving throw

Everything below adds together:

Spellcraft is a defence, not an attack: it raises the save of whoever is being hit, and does nothing for the DC of the spells you cast.

You have to buy the first rank yourself. Spellcraft that comes only from items and abilities adds nothing. Once a single skill point is in it, the whole skill counts - your ranks and every bonus on top of them - and a tenth of that is added.

It shares the 20-point cap with your items and effects. Only what is left of the cap is added, so at 20 from gear Spellcraft adds nothing at all, and at 14 from gear a Spellcraft of 100 adds 6 rather than 10.

These add on top, each against its own kind of effect:

Damage, saves and metamagic

On an area spell, Empower lengthens the area instead: half again as long, rather than half again as much damage.

A spell that needs a touch attack does double damage on a critical hit, with Harm the one exception.

Some spells damage doors and placeables as well as creatures, and a few of them - Earthquake, Destruction, Crumble, Horizikaul's Boom, Sound Burst, Hellball, Incendiary Cloud, sonic cones and howls - do double damage to them. Ice Storm, Meteor Swarm and Bombardment double only their second kind of damage.

How many areas you can keep up

Four, counting every area spell you have running. Casting a fifth destroys the oldest one.

Two of any single spell. A third Web of your own destroys your oldest Web, even if you are below the total of four.

Healing

Heal, Greater Restoration and Heal Ally restore all of a living target's hit points, whatever the description says about a number. Mass Heal does the same from caster level 30.

The Healing domain adds half again to everything a cleric heals with a spell.

Negative energy heals the undead. A spell whose only damage is negative energy heals an undead target instead of hurting it, with no attack roll, no saving throw and no spell resistance to get in the way.

When you cannot cast

• No-magic zones. Nothing is cast there, from a spellbook or from an item. Two exceptions: socketable gems, and the winged pendant.
• A potion cannot be used on another player. Only on yourself.
• Full healing potions have a cooldown, shared across all of them.
• A PvP tournament in progress stops casting in arena mode entirely. Healing spells and etherealness are counted against a cap while a tournament runs.

Warlocks and armour

A Warlock casting from their own spellbook reduces arcane spell failure before it is rolled:

Whatever is left is rolled on a d100, and the spell fails if the roll comes up under it. A stilled spell skips the check entirely.

What a Warlock spends

A Warlock does not spend slots the way other casters do. Casting an invocation from the spellbook takes its own level in slots, and metamagic raises what it costs:

Six invocations cost nothing at all once you have the feat that grants them:

Two things casting does to you

Expertise switches off. Starting to cast turns off both Expertise and Improved Expertise.

A scroll cannot be learned between levels. Level up first, then read it.

See also

• Spells
• Feats
• Spellcraft
• Abilities