BASIC D20 SPELLCASTING
Basic d20 assumes that you will use the normal D&D spellcasting system to create characters.
Characters will have a number of class-based spellcasting systems to choose from, such as cleric, druid,and wizard. A previous document, Basic d20 Magic Skills, detailed how each school of magic could bemade into its own skill, thus eliminating class-based spellcasting entirely. Basic d20 Spellcasting offers
an even simpler system: spellcasting based on the generic spellcaster from the SRD.

POWER: SPELLCASTING (5 PP PER LEVEL)
Spellcasters learn and cast spells as a sorcerer. They may select their spells known from the cleric,domain, druid, sorcerer/wizard spell lists and any other spell lists permitted by the GM. If a spell has
different spell levels for different classes, use the lowest from among cleric, druid, and sorcerer/wizard
classes (excluding domain lists). For example, true seeing becomes a 5th level spell under this system
and refuge is a 7th level spell for the spellcaster. If a spell is not found on any of these three lists, use
the lowest level listed for any class. For example, heal mount is only found on the paladin spell list. If
the GM permits this spell to be learned by spellcasters, then it is a 3rd level spell. Order’s wrath is only
found on the Law Domain spell list, so it is a 4th level spell for spellcasters.
Under this system, disregard the arcane/divine distinction in spellcasting. For any game effects that
require the source of the character’s spellcasting ability be known (whether arcane or divine), the GMshould exercise good judgment. Spellcasters are not affected by the arcane spell failure chance whenwearing armor in which they are proficient. Spellcasters wearing armor in which they are not proficientsuffer the normal arcane spell failure chances.
A character’s key ability is the highest of the character’s Intelligence, Wisdom, or Charisma ability score
modifiers. The key ability is added to the Difficulty Class of the saving throws for spells cast by thecharacter. Bonus spell slots are based on the key ability according to the table below. The key ability
also determines the highest spell level the character can learn.
HIGHEST SPELL LEVEL ABLE TO BE LEARNED = KEY ABILITY × 2 + 1
A simple table summarizes this formula:
Key Ability Score Modifier for Spellcasting+0+1+2+3+4

Highest Spell Level Able to be Learned or Cast
1st
3rd
5th
7th
9th

1

A spellcaster’s number of spells per day by spellcaster level and bonus spell slots are listed below.

Level

0th

1st

2nd

3rd

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20

4
5
566666
666666666666234
5
566
6
666
6
6666666623455666666666666234556666666666Spells per Day
4th5th2345566666666234556666666th

7th

8th

9th2
34
5566662345566234562
35Bonus Spells (By Spell Level)
Key Ability
Score Modifier-1 or lower+0+1+2+3+4+5+6+7+8+9+100th

1st2nd3rd-

1111222233111122223111122224th
5th
Can’t cast spells
11111112122222

6th

7th

8th

9th

1
1112111111111

A spellcaster’s number of spells known by spellcaster level is listed below.

Level

0th

1st

2nd

3rd

Spells Known
4th
5th

12
34
5
6
78910111213
1415
16
1718
1920

4
4
55
66
7
7
8899999
9999
9

223
34
4
5
55
5
5555
5555551223344555
555
5555

1223344444444441223344444444122334444446th

7th

8th

9th

122333333122333312233123THREE FEATS ESPECIALLY SUITED FOR SPELLCASTING
The feats detailed below are found in a number of d20 supplements and can be used to expand thespellcasting capabilities of characters in your campaign.

Arcane Preparation [General]
You can prepare an arcane spell ahead of time as a wizard does.
Prerequisite: You must be able to cast spells as a bard or sorcerer before you can take this feat.
Benefit: Each day, you are able to prepare one or more spells as a wizard does. If you are a sorcerer or abard, this means that you can prepare a spell with a metamagic feat ahead of time, instead of casting it
as a full-round action. The prepared spell remains in your mind and occupies one of your spell slots until
you cast it or change it. A prepared spell uses a spell slot of the spell’s normal level, modified by anyother metamagic feats.

3Extra Slot [General]You can cast an extra spell.
Prerequisites: Spellcaster level 4th+.
Benefit: You gain one extra spell slot in your daily allotment. This extra slot can be at any level up to one
level lower than the highest-level spell you can cast. For example, a 4th level sorcerer gains either an
extra 0-level or 1st-level slot, allowing him to cast any known spell of the chosen level one more timeeach day. A 4th-level wizard can prepare any extra 0-level or 1st-level spell she knows. Once selected,the extra spell slot never migrates up or down in level.
Special: You can gain this feat multiple times. Each time, you gain an extra spell slot at any level up toone level lower than the highest-level spell you can cast.

Extra Spell [General]
You can learn one more spell.
Prerequisites: Spellcaster level 3rd+.
Benefit: You learn one additional spell at any level up to one level lower than the highest-level spell youcan cast. Thus, a 4th-level sorcerer gains a new 0-level or 1st-level spell, expanding his repertoire. A 4thlevel wizard can likewise learn an extra 0-level or 1st-level spell, but since wizards learn spells far moreeasily than sorcerers, this feat is of less use to her.
Special: You can gain this feat multiple times. Each time, you learn a new spell at any level up to one
lower than the highest-level spell you can cast.

CAN IT GET ANY SIMPLER THAN THIS?
The answer is probably “No.” All spellcasting has been reduced to a 5 PP per level spellcasting power
based on the generic spellcaster class in the System Reference Document. Arcane and divineclassifications are discarded as well as all class-based spellcasting distinctions. Every spellcasterfunctions as a sorcerer but has access to all spell lists. Extra spells can be learned and extra spell slots
can be purchased for 1 PP each with the Extra Spell and Extra Slot feats. Spells can be prepared aheadof time if Arcane Preparation is taken. GMs can make any other feats available to expand the versatilityof this power. By adding the theurgy series of spells from D&D5E or the sorcery series of spells fromCustom Characters to your campaign, the spellcaster can also have the ability to spontaneously cast lowlevel spells thus increasing versatility even further.

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