So I'm getting back into BG again after a bit of a hiatus. And, since I was thinking about a specialist mage, I ended up in the situation where I was thinking "Crap, what spells do I lose if I go with this particular school?" I'm not aware of anything out there on the internet quite like this, so thought I'd share this list I made for all you aspiring specialist mage players out there.

Basically, it's the specialist school at the top of each list in bold. In brackets is the opposition school. Listed are the spells you lose if you decide to choose that specialization. So, here it is, and I hope some of you find it useful:

ABJURER (Alteration/Transmutation)

(1)Burning Hands
Color Spray
Shocking Grasp
(2)Strength
Vocalize
(3)Haste
Slow
(4)Dimension Door
Otiluke's Resilient Sphere
Polymorph Other
Polymorph Self
Stoneskin
Teleport Field
Wizard Eye
(5)none
(6)Disintegrate
Flesh to Stone
Improved Haste
Stone to Flesh
Tenser's Transformation
(7)Ruby Ray of Reversal
Sphere of Chaos
(8)none
(9)Shapechange
Time Stop

CONJURER (Divination)

(1)Identify
Infravision
(2)Detect Evil
Detect Invisibility
Know Alignment
(3)Clairvoyance
Detect Illusion
(4)Farsight
(5)Oracle
(6)True Sight
(7)none
(8)none
(9)none

DIVINER (Conjuration)

(1)Armor
Find Familiar
Grease
(2)Glitterdust
Melf's Acid Arrow
Power Word: Sleep
(3)Flame Arrow
Ghost Armor
Monster Summoning I
(4)Monster Summoning II
Spider Spawn
(5)Conjure Lesser Air Elemental
Conjure Lesser Earth Elemental
Conjure Lesser Fire Elemental
Monster Summoning III
(6)Carrion Summons
Conjure Air Elemental
Conjure Earth Elemental
Conjure Fire Elemental
Invisible Stalker
Power Word: Silence
Summon Nishruu
Wyvern Call
(7)Cacofiend
Limited Wish
Power Word: Stun
Prismatic Spray
Summon Djinni
Summon Efreeti
Summon Hakeashar
(8)Maze
Power Word: Blind
Summon Fiend
Symbol: Death
Symbol: Fear
Symbol: Stun
(9)Gate
Power Word: Kill

ENCHANTER (Evocation)

(1)Chromatic Orb
Magic Missile
Shield
(2)Agannazar's Scorcher
Stinking Cloud
Web
(3)Fireball
Lightning Bolt
Melf's Minute Meteors
(4)Ice Storm
Fireshield: Blue
Fireshield: Red
Minor Sequencer
(5)Cloudkill
Cone of Cold
Phantom Blade
Sunfire
(6)Chain Lightning
Contingency
Death Fog
(7)Delayed Blast Fireball
Mordenkainen's Sword
Spell Sequencer
(8)Bigby's Clenched Fist
Incendiary Cloud
Spell Trigger
(9)Bigby's Crushing Hand
Black Blade of Disaster
Chain Contingency
Meteor Swarm

ILLUSIONIST (Necromancy)

(1)Chill Touch
Larloch's Minor Drain
(2)Ghoul Touch
Horror
(3)Hold Undead
Skull Trap
Vampiric Touch
(4)Contagion
Spirit Armor
(5)Animate Dead
(6)Death Spell
(7)Control Undead
Finger of Death
(8)Abi-Dalzim's Horrid Wilting
(9)Energy Drain
Wail of the Banshee

INVOKER (Enchantment)

(1)Charm Person
Friends
Sleep
(2)Luck
Ray of Enfeeblement
(3)Dire Charm
Hold Person
(4)Confusion
Emotion: Hopelessness
Enchanted Weapon
Greater Malison
(5)Chaos
Domination
Feeblemind
Hold Monster
(6)none
(7)none
(8)none
(9)none

NECROMANCER (Illusion)

(1)Blindness
Reflected Image
Spook
(2)Blur
Deafness
Invisibility
Mirror Image
(3)Invisibility 10' Radius
(4)Improved Invisibility
(5)Shadow Door
(6)Mislead
(7)Project Image
Mass Invisibility
(8)Simulacrum
(9)none

TRANSMUTER (Abjuration)

(1)Protection from Evil
Protection from Petrification
(2)Resist Fear
(3)Dispel Magic
Minor Spell Deflection
Non-Detection
Protection from Cold
Protection from Fire
Protection from Normal Missiles
Remove Magic
Spell Thrust
(4)Minor Globe of Invulnerability
Remove Curse
Secret Word
(5)Breach
Lower Magic Resistance
Minor Spell Turning
Protection from Acid
Protection from Electricity
Protection from Normal Weapons
Spell Immunity
Spell Shield
(6)Globe of Invulnerability
Pierce Magic
Protection from Magic Energy
Protection from Magical Weapons
Spell Deflection
(7)Khelben's Warding Whip
Mantle
Protection from the Elements
Spell Turning
(8)Improved Mantle
Protection from Energy
(9)Absolute Immunity
Freedom
Imprisonment
Spellstrike
Spell Trap

It's a great idea, and of course to you (who made it) it makes perfect sense, but I can see newbies being confused by the list. You mention parenthesis but don't mention what the figures in parenthesis are -- I know they're spell levels, but will a newbie? So, I reformatted your list to:

ABJURER (Opposition: Alteration/Transmutation)

(Level 1 spells lost)
Burning Hands
Color Spray
Shocking Grasp

(Level 2 spells lost)
Strength
Vocalize

(Level 3 spells lost)
Haste
Slow

(Level 4 spells lost)
Dimension Door
Otiluke's Resilient Sphere
Polymorph Other
Polymorph Self
Stoneskin
Teleport Field
Wizard Eye

(Level 5 spells lost)
none

(Level 6 spells lost)
Disintegrate
Flesh to Stone
Improved Haste
Stone to Flesh
Tenser's Transformation

(Level 7 spells lost)
Ruby Ray of Reversal
Sphere of Chaos

(Level 8 spells lost)
none

(Level 9 spells lost)
Shapechange
Time Stop


CONJURER (Opposition: Divination)

(Level 1 spells lost)
Identify
Infravision

(Level 2 spells lost)
Detect Evil
Detect Invisibility
Know Alignment

(Level 3 spells lost)
Clairvoyance
Detect Illusion

(Level 4 spells lost)
Farsight

(Level 5 spells lost)
Oracle

(Level 6 spells lost)
True Sight

(Level 7 spells lost)
none

(Level 8 spells lost)
none

(Level 9 spells lost)
none


DIVINER (Opposition: Conjuration)

(Level 1 spells lost)
Armor
Find Familiar
Grease

(Level 2 spells lost)
Glitterdust
Melf's Acid Arrow
Power Word: Sleep

(Level 3 spells lost)
Flame Arrow
Ghost Armor
Monster Summoning I

(Level 4 spells lost)
Monster Summoning II
Spider Spawn

(Level 5 spells lost)
Conjure Lesser Air Elemental
Conjure Lesser Earth Elemental
Conjure Lesser Fire Elemental
Monster Summoning III

(Level 6 spells lost)
Carrion Summons
Conjure Air Elemental
Conjure Earth Elemental
Conjure Fire Elemental
Invisible Stalker
Power Word: Silence
Summon Nishruu
Wyvern Call

(Level 7 spells lost)
Cacofiend
Limited Wish
Power Word: Stun
Prismatic Spray
Summon Djinni
Summon Efreeti
Summon Hakeashar

(Level 8 spells lost)
Maze
Power Word: Blind
Summon Fiend
Symbol: Death
Symbol: Fear
Symbol: Stun

(Level 9 spells lost)
Gate
Power Word: Kill


ENCHANTER (Opposition: Evocation)

(Level 1 spells lost)
Chromatic Orb
Magic Missile
Shield

(Level 2 spells lost)
Agannazar's Scorcher
Stinking Cloud
Web

(Level 3 spells lost)
Fireball
Lightning Bolt
Melf's Minute Meteors

(Level 4 spells lost)
Ice Storm
Fireshield: Blue
Fireshield: Red
Minor Sequencer

(Level 5 spells lost)
Cloudkill
Cone of Cold
Phantom Blade
Sunfire

(Level 6 spells lost)
Chain Lightning
Contingency
Death Fog

(Level 7 spells lost)
Delayed Blast Fireball
Mordenkainen's Sword
Spell Sequencer

(Level 8 spells lost)
Bigby's Clenched Fist
Incendiary Cloud
Spell Trigger

(Level 9 spells lost)
Bigby's Crushing Hand
Black Blade of Disaster
Chain Contingency
Meteor Swarm


ILLUSIONIST (Opposition: Necromancy)

(Level 1 spells lost)
Chill Touch
Larloch's Minor Drain

(Level 2 spells lost)
Ghoul Touch
Horror

(Level 3 spells lost)
Hold Undead
Skull Trap
Vampiric Touch

(Level 4 spells lost)
Contagion
Spirit Armor

(Level 5 spells lost)
Animate Dead

(Level 6 spells lost)
Death Spell

(Level 7 spells lost)
Control Undead
Finger of Death

(Level 8 spells lost)
Abi-Dalzim's Horrid Wilting

(Level 9 spells lost)
Energy Drain
Wail of the Banshee


INVOKER (Opposition: Enchantment)

(Level 1 spells lost)
Charm Person
Friends
Sleep

(Level 2 spells lost)
Luck
Ray of Enfeeblement

(Level 3 spells lost)
Dire Charm
Hold Person

(Level 4 spells lost)
Confusion
Emotion: Hopelessness
Enchanted Weapon
Greater Malison

(Level 5 spells lost)
Chaos
Domination
Feeblemind
Hold Monster

(Level 6 spells lost)
none

(Level 7 spells lost)
none

(Level 8 spells lost)
none

(Level 9 spells lost)
none


NECROMANCER (Opposition: Illusion)

(Level 1 spells lost)
Blindness
Reflected Image
Spook

(Level 2 spells lost)
Blur
Deafness
Invisibility
Mirror Image

(Level 3 spells lost)
Invisibility 10' Radius

(Level 4 spells lost)
Improved Invisibility

(Level 5 spells lost)
Shadow Door

(Level 6 spells lost)
Mislead

(Level 7 spells lost)
Project Image
Mass Invisibility

(Level 8 spells lost)
Simulacrum

(Level 9 spells lost)
none


TRANSMUTER (Opposition: Abjuration)

(Level 1 spells lost)
Protection from Evil
Protection from Petrification

(Level 2 spells lost)
Resist Fear

(Level 3 spells lost)
Dispel Magic
Minor Spell Deflection
Non-Detection
Protection from Cold
Protection from Fire
Protection from Normal Missiles
Remove Magic
Spell Thrust

(Level 4 spells lost)
Minor Globe of Invulnerability
Remove Curse
Secret Word

(Level 5 spells lost)
Breach
Lower Magic Resistance
Minor Spell Turning
Protection from Acid
Protection from Electricity
Protection from Normal Weapons
Spell Immunity
Spell Shield

(Level 6 spells lost)
Globe of Invulnerability
Pierce Magic
Protection from Magic Energy
Protection from Magical Weapons
Spell Deflection

(Level 7 spells lost)
Khelben's Warding Whip
Mantle
Protection from the Elements
Spell Turning

(Level 8 spells lost)
Improved Mantle
Protection from Energy

(Level 9 spells lost)
Absolute Immunity
Freedom
Imprisonment
Spellstrike
Spell Trap

I actually thought of that and waffled a bit about whether or not to add the clarification. In the end, I figured it would be obvious, but it never hurts to be clearer, so thanks for taking the time to enhance it. :)

Great post:)

Are we sure the invoker doesn't lose the conjuration spells too? I remember Baldur's Gate being a bit different than official D&D rules but I only remember Conjurer was specially treated.

PS: I played the original not the enhanced editions.

If I am correct, may I contribute by copying and pasting

INVOKER (Opposition: Conjuration)

(Level 1 spells lost)
Armor
Find Familiar
Grease

(Level 2 spells lost)
Glitterdust
Melf's Acid Arrow
Power Word: Sleep

(Level 3 spells lost)
Flame Arrow
Ghost Armor
Monster Summoning I

(Level 4 spells lost)
Monster Summoning II
Spider Spawn

(Level 5 spells lost)
Conjure Lesser Air Elemental
Conjure Lesser Earth Elemental
Conjure Lesser Fire Elemental
Monster Summoning III

(Level 6 spells lost)
Carrion Summons
Conjure Air Elemental
Conjure Earth Elemental
Conjure Fire Elemental
Invisible Stalker
Power Word: Silence
Summon Nishruu
Wyvern Call

(Level 7 spells lost)
Cacofiend
Limited Wish
Power Word: Stun
Prismatic Spray
Summon Djinni
Summon Efreeti
Summon Hakeashar

(Level 8 spells lost)
Maze
Power Word: Blind
Summon Fiend
Symbol: Death
Symbol: Fear
Symbol: Stun

(Level 9 spells lost)
Gate
Power Word: Kill

And what about level 10 spells (special abilities)? Were some prohibited?

Looks like, from a power perspective, that the best specialist mages will tend to be Conjurers (loses Identify and True Seeing), followed by Invokers (loses crowd control and disables), followed by Necromancers (loses various levels of invisibility).

Only in the original BG1. BG2 was brought back into line with only Enchantment being in opposition. They are counted as high level abilities, not spells and none are prohibited by school, only alignment (Deva vs Fallen Deva, for example).

Great post, OP. Great post.

Confirms Edwin Odesseiron as absurdly strong.

+1 to both Groot and Hickory. Great work guys (or girls).

Yep, it's the reason I installed the no rep mod. The good guys have barely any passable mages unless your PC is one.

Screw Minsc.