Alright, here are the spellcaster units. Each one does something radically different, and you can base whole strategies off them. They might not be balanced (Worrying about the Viking Sorcerors and the Teutonic Necromancers) and this is assuming it's programmable. Might very well not be. Here's a list of what nation gets what Spellcaster. It's not that historically accurate, so any advice is helpful.
Asian civs
China-Sage
India-Lama
Japan-Healer
Mongolia-Siddhar
Arabia-Magi
European Civs
England-Wizard (The land of Harry Potter and Merlin)
France-Druids
Teutons-Necromancer
Spain-Alchemist
Vikings-Sorceror
Okay, once you get them, Spellcasters can sacrifice themselves to cast a one time specific spell. Then, later in the game, you have two choices, Light or Dark. Each way gives a different spell you can cast, and a small bonus that is passive (i.e., plus 1 movement, invisible to enemies, etc.) You can still cast the old spell, and then the Dark spell or the Light spell. One you have chosen one way you can never go back. Here's what each spellcaster does:
Spellcasters
Arabia
Magi
Divination-can give 20% of the beakers needed to a technology
Dark-makes unit invisible to most units
Fog the future- Can enter an enemy city. That city provides no research for the next 3 turns.
Or
Light-heals units in same stack additional 5%
Revelation-Discovers a random technology you have the prerequisites for. It gives all nations the same technology if they have the prerequisites.
India
Lama
Consecration-Can give priest, bishop, archbishop, or cardinal an additional +2 coin
Dark-Can only be built in city with state religion
Religious Persecution-can remove a religion from one of your cities
Or
Light-Can only be built in city with state religion
Religious Tolerance- Can put any religion in a city that is already present in at least one of your cities.
Chinese
Sage
Proverbs-Can give a unit +2 exp
Dark-Invisible to most units
Shao-Lin Martial Arts- Gains combat 40 for one turn, then dies next turn.
Or
Light- Gains +1 movement
Sensei-can join city as a specialist. Gives all units made there +1 exp
Japanese
Healer
Cure-Returns one unit to full health
Dark-Invisible to most units
Sabotage Healing-Can keep one unit from healing for the next five turns.
Or
Light-Heals all units in stack additional 10% per turn
Ritual Healing-All units in stack are healed to full health
Mongolia
Siddhar
Mantra-Can give an economic unit, religious unit, or settler +1 movement point.
Dark-Invisible to most units
Create cult-can create a cult in a city, gives it three turns of revolt.
Or
Light-50% withdrawal chance
Conversion-Can “convert” an enemy unit to become yours, must have less than 17 exp.
English
Wizard (the land of Merlin)
Fortune- Can bless a town to produce +1 coin
Dark-invisible to most units
Ruin Land-Can make a tile produce –1 food
Or
Light-gives an additional 5% healing to units in the same stack
Abundance-Can make a tile produce +1 food
France
Druid
Construct Henge-Builds a Henge in a city. Myth units and Spellcasters produced 20% faster
Dark-Can only be built in a city with a Henge.
Initiate Dark Age-Sends all civilizations into 4 turns of .
Or
Light-Gives city it’s in +1 production, can build 4 at a time.
Construct Temple-Can build Pagan Temple in a city, acts like normal temple but requires no religion. Effects obsolete if there is a religion in the city
Teutonic Tribes
Necromancer
Invocation of the -Creates three Zombies, 8 combat, I move, +50% vs. Myth
Dark-Costs twice normal amount for Spellcaster
Summon Shade-Summons a Shade, gives Fear to all enemy units around it. Fear gives –10% combat, loses withdrawal chance and first strikes.
Or
Light-Costs twice normal amount for Spellcaster
Summon Angel-Summons an Angel, who gives Inspiration to all units in the same stack. Inspiration-Gives all units +10% combat, +20% healing rate, and +20% withdrawal chance.
Spain
Alchemist
Construct Alchemist’s Workshop-Can build a Workshop in a city that gives +5 coins for each bronze and each iron resources you have.
Dark-Gives city it’s in +2 production with Bronze, +2 production with Iron, can only build 4 at a time.
Construct Siegeworks- Siege units get +50% production with Bronze, +50% production with Iron
Or
Light-Requires Alchemist’s Workshop to build
The Philosopher’s Stone-Can create the resource gold on a hill.
Vikings
Sorcerer
Bless-Gives unit Bless. Bless-gives unit +10% combat.
Dark-Gets a +1 movement rate
Power of -Give unit Power of . Power of -Gets +50% vs. Secular Units (Not-Myth)
Or
Light-Heals units in same stack an additional +5% per turn
Resistance-Gives unit Resistance. Resistance-Gets +50% vs. Myth Units.
