Simplified Rules
Choose a Magician type and start each Adventure with that spell set and can cast each spell once in the normal way. Rules and stats are the same as the Wizard except they can't use magic weapons or armour other than those that are specifically for Magicians (such as Bracers and Cloaks Of Protection) or that are items that they can normally use (such as Staffs). I gave them different names using colours so you can give the players the option of using either or both versions.
Mystic/Brown Wizard: Choose a spell set before the start of each Adventure using the rules of that Magician type, moves with lowest two of three dice.
Abjurer/White Wizard: Can transfer any amount of your own MP to BP or BP to MP during your turn without using an action.
Conjurer/Green Wizard: Roll a combat dice at the start of the next Hero phase for each summoned Monster, skull = remove from play, white shield = becomes your Follower, black shield = now under EWP control.
Diviner/Yellow Wizard: Five rerolls per Adventure but can't reroll the same dice more than once.
Enchanter/Red Wizard: All of your attacks are magical attacks.
Evoker/Blue Wizard: Can attack with fire, ice and lightning based attacks and immune to fire, ice and lightning based attacks.
Illusionist/Orange Wizard: Defends on black as well as white shields.
Nekromancer/Purple Wizard: Summoned/resurrected/etc monsters are treated as your Followers until the end of the Adventure or until they die.
Transmuter/Black Wizard: Can use your attacking action to change any Potion in your possession into a different random Potion, each Potion can only be changed once.
Opposition Schools
You can't use Scrolls of your opposition School, Mystics/Brown Wizards can use Scrolls from any School.
Abjuration/White - Transmutation/Black
Conjuration/Green - Divination/Yellow
Enchantment/Red - Evocation/Blue
Illusion/Orange - Nekromancy/Purple
Veteran: You can cast a spell (two spells the Wand Of Recall/Magic) at any time during the Hero phase as long as you still have your attacking action and the permission of the player if you're interrupting their turn.
Master: You can cast a spell (two spells the Wand Of Recall/Magic) during the EWP phase but not during a Monster's turn, if you used your attacking action on your previous turn then you lose your attacking action on your next turn.
Legend: You can cast one spell (two spells the Wand Of Recall/Magic) during each EWP phase but not during a Monster's turn and you don't lose an action.
Colour Mage: Same thing with elves, BP3/MP7 and move with the highest two of three dice or with two dice for Brown Mages.
Colour Sorcerer: Same thing with Monsters but without the special rules and with some replacement spells, for Brown Sorcerers the EWP chooses when they're revealed, M6 A2 D3 BP2 MP4, three random spells.
Champion: BP3 MP5, five random spells.
Master: BP4 MP6, seven random spells.
Lord: BP5 MP7, all nine spells.
Clairvoyance, Treasure Horde and Treasure Without Doom replaced by Call Orcs, Orc Berserker and Sharpen Blades.
Disappear replaced by Escape.
Ice Bridge replaced by Call Goblins.
Call Orcs and Call Goblins are Summon Orcs and Summon Goblins from the Wizards Of Morcar orc shaman set, renamed to Call to make them different from the US version and because of how they work.
Magic-Users
Magic-User is a term for Magicians that have access to a wide pool of spells (hence the generic term) and don't take as long as other Magicians to recharge them. Other than their spell rules they have the same rules and stats as the Wizard except they move with the lowest two of three dice and can't use magic weapons or armour other than those that are specifically for Magicians (such as Bracers and Cloaks Of Protection) or that are items that they can normally use (such as Staffs). They need to absorb their spells into their minds in a process called Memorisation before they can be cast, which is done prior to an adventure and can also be done during adventures but the energy tends to attract unwanted visitors. They can only Memorise spells that are written in their Spell Book which can be added to by Scribing spells from Scrolls. Most Magic-Users specialise in a specific School of magic but still have access to most of the other Schools, while others (Mystics) have access to all Schools but can't hold quite as many spells in their Memory at a time.
Magic-User spells are split into eight Schools, each with an opposing School. Specialists of one School can't cast spells from their opposing School (not even from Scrolls), however they can Memorise two extra Level 1 spells and one extra Level 2 spell but they can only hold a maximum of twelve spells from other Schools in their Memory at a time.
Abjuration: Spells of protection, blocking, and banishing. Specialists are called Abjurers.
Dispell, Heal Body, Ice Wall, Mirror Magic, Remove Spell, Restore Chaos, Shield Of Protection, Soothe, Water Of Healing.
Conjuration: Spells that bring creatures or materials. Specialists are called Conjurers.
Arrows Of The Night, Ball Of Flame, Chains Of Darkness, Cloud Of Chaos, Fire Of Wrath, Genie, Strands Of Binding, Summon Orcs, Summon Wolves.
Divination: Spells that reveal information. Specialists are called Diviners.
Clairvoyance, Flashback, Future Sight, Skate, Slow, Time Stop, Transport, Treasure Hoard, Treasure Without Doom.
Enchantment: Spells that magically imbue the target or give the caster power over the target. Specialists are called Enchanters.
Command, Courage, Deep Sleep, Dominate, Mind Blast, Mind Freeze, Mind Lock, Mind Numb, Sleep.
Evocation: Spells that manipulate energy or create something from nothing. Specialists are called Evokers.
Blinding Sleet, Firestorm, Hurricane, Ice Storm, Lightning Blast, Lightning Bolt, Swift Wind, Thieving Wind, Tempest.
Illusion: Spells that alter perception or create false images. Specialists are called Illusionists.
Cloak Of Shadows, Double Image, Disappear, Fear, Hypnotic Blaze, Invisibility, Madness, Terror, Vail Of Mist.
Necromancy: Spells that manipulate life or life force. Specialists are called Nekromancers.
Call Skeletons, Chill, Death Bolt, Raise The Dead, Reanimation, Skull Of Doom, Spirit Of Vengeance, Summon Mummy, Summon Undead.
Transmutation: Spells that transform the target. Specialists are called Transmuters.
Decay, Earthquake, Pass Through Rock, Rock Skin, Rust, Twist Wood, Warewolf's Curse, Wall Of Stone, Ice Bridge.
Necromancer's Fear renamed to Terror, Storm Master's Lightning Bolt renamed to Lightning Blast, High Mage's Dispel, Escape and Rust renamed to Remove Spell, Transport and Decay and Mage Of The Mirror's Mind Blast renamed to Mind Numb. Rust, Fear, Summon Orcs, Dispell and Lightning Bolt are from the chaos deck, Mind Blast is a Chaos Sorcerer token from Against the Ogre Hoard along with Mind Lock and Dominate. If you're using my Talisman spells there's already a Lightning Bolt and Invisibility so you could rename the existing ones to Lightning Strike and Vanish.
Roll a combat dice at the start of the next Hero phase for each summoned Monster, skull = remove from play, white shield = becomes your Follower, black shield = now under EWP control.
Opposition Schools
Abjuration and Transmutation
Conjuration and Divination
Enchantment and Evocation
Illusion and Necromancy
The number of spells Mystics can hold in their Memory of each Level is (counting up): 3, 2, 2, 2, 2, 1. So for Specialists it's: 5, 3, 2, 2, 2, 1. Specialists start with all the spells of their School in their Spell Book and choose six other Level 1 spells, five other level 2 spells, four other Level 3 spells, etc. Mystics choose eight Level 1 spells, seven Level 2 spells, six Level 3 spells, etc. Magic-Users can't hold more than two healing spells in their Memory at a time or hold spells that are a higher Level than their current MP, if their MP is reduced then any spells in their Memory of a higher Level than their current MP are forgotten. Keep the spells in your Spell Book and Memory hidden from the EWP.
Level 1 Spells
Blinding Sleet, Clairvoyance, Hurricane, Ice Bridge, Invisibility, Remove Spell, Shield Of Protection, Skull Of Doom, Swift Wind, Treasure Hoard, Treasure Without Doom, Vail Of Mist.
Level 2 Spells
Arrows Of The Night, Chill, Courage, Fear, Ice Wall, Lightning Blast, Raise The Dead, Pass Through Rock, Rock Skin, Skate, Sleep, Warewolf's Curse.
Level 3 Spells
Call Skeletons, Death Bolt, Dispell, Dominate, Earthquake, Fire Of Wrath, Reanimation, Summon Mummy, Terror, Thieving Wind, Transport, Wall Of Stone.
Level 4 Spells
Ball Of Flame, Chains Of Darkness, Deep Sleep, Disappear, Double Image, Flashback, Hypnotic Blaze, Slow, Soothe, Spirit Of Vengeance, Timestop, Twist Wood.
Level 5 Spells
Cloak Of Shadows, Command, Future Sight, Genie, Heal Body, Mind Blast, Mind Lock, Mirror Magic, Rust, Summon Undead, Tempest, Water Of Healing.
Level 6 Spells
Cloud Of Chaos, Decay, Firestorm, Ice Storm, Lightning Bolt, Madness, Mind Freeze, Mind Numb, Restore Chaos, Strands Of Binding, Summon Orcs, Summon Wolves.
To Memorise spells the Magic-User needs to be in a room with no Monsters. You can Memorise any amount of spells of a single Level in one turn but you can doing nothing else during a turn that you Memorise spells. For Level 1-5 spells roll one dice to Memorise one spell, two dice to Memorise two or three spells, three dice to Memorise four-six spells and four dice to Memorise more than six spells. You can discard spells before doing this to make room for new ones. All the dice need to be higher than the spell Level, if any are equal to or lower than the spell Level a Wandering Monster is triggered before the spells are Memorised. To Memorise a Level 6 spell you need to score eleven or twelve on two dice, roll separately for each spell.
Magic-Users can only Memorise spells that are in their Spell Book but are able to Learn new Magic-User spells by Scribing them from Scrolls. Scribing is done in the same way as Memorising and you can Memorise and Scribe spells of the same Level during the same turn but you can't Scribe and Memorise the same spell during the same turn. Scribed Scrolls are discarded.
Mystics
Novice: 3, 2, 2, 2, 2, 1.
Veteran: 4, 3, 3, 2, 2, 1. Choose one new spell of each Level to Learn.
Master: 5, 4, 3, 3, 2, 1. Choose one new spell of each Level to Learn.
Legend: 5, 4, 4, 3, 3, 2. Choose one new spell of each Level to Learn.
Specialists
Novice: 5, 3, 2, 2, 2, 1. Maximum of twelve spells from other Schools.
Veteran: 6, 4, 3, 2, 2, 1. Maximum of fifteen spells from other Schools. Choose one new spell of each Level to Learn.
Master: 7, 5, 3, 3, 2, 1. Maximum of eighteen spells from other Schools. Choose one new spell of each Level to Learn.
Legend: 7, 5, 4, 3, 3, 2. Maximum of twenty-one spells from other Schools. Choose one new spell of each Level to Learn.
1BP, 
2BP, 
3BP, 
1BP, 
2BP, 
3BP, 
4BP, 
5BP. US 
I've just renamed some because the two different versions use some spells with the same names.