A mage type is selecting when you reach Mage Experience Level 3 (ML3). You usually reach this level halfway through Dungeon Level 3 (DL3). You are forced to pick your Mage Type first, then you can pick your spell for reaching XP Level 3.

Level up order:
1) Pick mage type (if at ML3)
2) Pick spell
3) Pick stats (at end of current DL/start of next DL)

If you pick the Gambler mage type, you'll see the benefit of the extra spell choice immediately. If you pick the Spellmason mage type, you won't see the benefit of an extra stat point until you complete your current DL.
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Mage type is a permanent choice for a given run. Any spells gained from a mage type are in addition to your choice of spells from levelling.

ToDo:
-What happens if you already have the spell granted by a mage type? Does it upgrade or do you get nothing?
-If you have the Mana Capture Soul perk, is that in addition to the Necromancer's Health Capture Soul perk, or is your existing spell transformed into the new version?
-How fast are ML's gained compared to DL's? Is it about 1 ML per 1 DL, is it a different scaling, is up to RNG? Does it depend on enemy types?
-How does multiplayer levelling work? Is EXP shared?
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When selecting a mage type, you may notice a blue map icon at the bottom of the mage type card. This shows you the highest dungeon level you've reached with that mage type, and - if you've won - how many wins you've had with that mage type.
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Since you'll be reaching ML3 when you make the choice, you'll be making your choice based on the following factors:

1) What are the 6 spells I've unlocked so far, and what do they synergize with?
2) Which 3 stat points did I spend so far?
3) Personal preference. At this early stage of the game, you can make any choice work.

https://gtm.steamproxy.vip/ugc/2485493794730193217/CE9966A61ADBC3FE21A73AC0B1A666BA49ED2F96/?imw=256&&ima=fit&impolicy=Letterbox&imcolor=%23000000&letterbox=false

Spellmason
Gain 4 stats per level up instead of 3, representing +25% more stats.

Timemason
Gain double the mana, but lose 1% mana per second.

Necromancer
Gain the Capture Soul spell, which costs 40 health instead of 60 mana. Summon spells are cheaper.

Archer
Gain the Arrow spell. Arrow spells costs do not increase when cast multiple times in the same turn.

Far Gazer
Double cast range, halve stamina.

Cleric
Gain the Heal spell. Blessings cost half mana.

Witch
Gain the Contaminate spell. Curses cost less to cast.

Gambler
Choose from 4 spells instead of 3 when gaining spells.

Gain 4 stats per ML instead of 3.

For reference, here is the value of stats:

Stat - Base Value - Stat Point Bonus
HP - 60 - 20
Mana - 60 - 5
Stamina - 200 - 20
Cast Range - 200 - 20
Good Looks - 0 - 0

How you spend your stats is up to preference, but keep in mind the following:
-If you consistently spend at least 1 point on Range but never on Stamina, you might have been better off with Far Gazer.
-If you consistently spend at least 1 point on Health, you might get more mileage out of the Cleric.
-If you consistently spend at least 1 point on Mana AND have great reflexes, you *might* want to give Timemason a try.

Gain double the mana, but lose 1% mana per second.

-You come out ahead as long as you take less than 50 seconds to use all you're mana.
-Once you are out of mana, take all the time you need to plan your next turn.
-Since stat points spent on Mana have about double the value, consider spending at least 1-2 stat points per ML on mana.

Gain the "Capture Soul" spell, but it costs 40 health (instead of 60 mana).
Summon spells cost less mana. (ToDo: How much less? 25%? A discount golem costs 42.)

=Capture Soul Spell=
-If the target has 31 health or less, kill it and turn it into a spell card that can be used to summon that unit.

-This still kills the target if you've already captured that enemy type before.

-Cannot give more than one spell card per specific enemy. Enemy variants (bosses, altered types, etc) count as distinct enemy types that are captured and summoned separately. Enemies with different status effects (such as being Split by the Cloning spell) do not count as distinct types.

-If none of the targets of the spell are under 31 health, the cost of this spell is automatically refunded.


An incredibly fun mage type with lots of potential, but can be tricky to use in practice.
-You need both HP and Mana to cast, so you need a wider stat spread.
-The icons that predict whether you'll be attacked next turn don't take the deaths of your minions into account. You'll have to predict turns yourself.
-Try not to rely on your summons for everything. They are too slow and simple minded to effectively solve some situations.
-Since your goal is to not only survive each level, but also capture each enemy type, it's easy to die of either being too greedy or not greedy enough.

ToDo: Can you farm EXP by abusing enemy summoners? Probably not, but it's worth investigating the details of EXP.

Gain the Arrow spell. All Arrow Spells have the same mana cost no matter how many times you cast them per turn.

=Arrow (10 mana?)=
10 Damage.

List of arrow spells:
Arrow, Upgraded Arrow, etc
Shadow Arrow
Target Arrow

Note that although arrow spells themselves have infinite range, they can't carry spell effects with them (with the obvious exception of Target Arrow).

This is a very powerful mage type early on, but is probably the weakest mage type in the long run. It can still work, but like all mage types, planning and synergy is needed.

Double cast range, half stamina.

Like all mage types that alter stats, the order in which you get your stats don't matter. You get double the range, whether you spent those stat points before or after getting this mage type.

To break even with the Spell Mason in terms of range, you need to spend at least 1 point per level on Range. To come out ahead - and make up for the lack of stamina - you need to spend 1-2 points per level on range. That only leaves 1-2 points to spend on mana and health, which is obviously quite limiting.

You have to be very efficient in how mana is spent to make this mage type work.

This mage type is probably stronger in multiplayer than in single player, though I could be wrong.

Gain the Heal spell.
Blessings cost half as much to cast.

=Heal (15 mana?)=
Heal 40? health.

Blessings include:
Heal, Greater Heal, etc.
Shield
Last Will
Purify

Blessings DO NOT include:
Toxic Resurrect, Clone, Send Mana, etc.

Unconfirmed:
Weak Resurrect, Resurrect

An incredibly powerful but specialized mage type that requires rare synergy to shine. Many of the most powerful (and rare) spells come with a health cost, and healing becomes incredibly cost effective when used in an AOE. That said, healing is not damage, so you'll still need to figure out how to kill things.

Blood Curse + Heal is a great early game damage dealer, but can be prohibitively expensive and counterproductive against late game enemies. There's obvious synergy with summoning and multiplayer.

Gain the Contaminate spell
Curses cost (-25%?) less to cast

Curses include:
Suffocation
Poison
Bloat
Cloning?
ToDo: What about Freeze, Slow, etc?

A very powerful class in terms of overall DPS, but struggles to kill things instantly. Requires specific and rare synergies to shine. Strongest when it has delaying tactics that buy time to get the curse engine rolling.

Strong synergy with summoning, delaying, curses, and multiplayer.

Choose from 4 spells instead of 3.

Although this is the weakest mage type in terms of stats, it's potentially the strongest if you know what spells to look for. Due to how the reroll mechanic works, you actually get +66% spells to choose from, not +25%.

Each time you reroll your spell choices, you get -1 choices to choose from, so the Gambler actually gets a lot more spell choices than the obvious +1 on the tooltip.

Normal Spellmason:
6 Spell choices. 3 + 2 after one reroll + 1 after two rerolls.

Gambler
10 Spell choices. 4 + 3 after one reroll +2 after two rerolls +3 after three rerolls.

How useful this mage type is depends on which spells you are looking for, how well you understand them, and how high of a level you reach. In theory, if you survive long enough, you can obtain every useful spell in the game, at which point this mage type becomes a complete dud. By that point you'll have long since "beaten" the game and found a way to sustainably defeat the post game levels, so said point is a tad moot.

Strong synergy with multiplayer, where friends can help carry you until you can find a gamebreaking spell combo. (And I do mean gamebreaking - I've gotten to postgame level 6+ with the right spell combo.)

Although all mage types are viable, some are far stronger in the context of teamwork. Some mage types have raw power, which is generally good. Others lack raw general power but have more effective reach. Lastly, some classes are quite weak unless someone buys them enough time to get the ball rolling.

As of Build 28, every DL past 12 is considered the postgame, which means multiple waves of enemies will spawn on a given level.

=Raw Power=
Spellmason - Easiest for newbies, best flexibility, highest potential mana aside from the Timemason.

Timemason - Great for experienced players, keeps turns short, not having time to plan is a less serious problem if you are covered by a buddy who can carefully clean up after you launch your initial spells.

=Finesse=
Archer - Very good at focus fire and picking off weakened targets. Great in large open levels, struggle in confined levels when fighting foes that ignore LOS. Definitely the weakest class overall in the post-game, but it has a niche until then.

Far Gazer - Can focus on dangerous minibosses from a safe range, while other mages use their superior firepower on closer and more immediate threats. Falls off slightly in the post game levels, where the sheer quantity of enemies - and abundance of range boosting targeting spells - makes range less relevant.

=Support=
Necromancer - This class really struggles to get a critical mass of summons going without help. Very powerful in the post-game levels, since summons stick around between waves, but surviving the first wave can get tricky.

Cleric - It's a Healer. Strong synergy with necromancers, spells that cost health, and crazy Spellmasons that spend all their stats on HP.

Witch - Like the Necromancer, getting the ball rolling can require some setup. Unlike the necromancer, keeping the ball rolling in post-game waves is quite tricky unless you have some sturdy summons/friends to "gift" your stack of curses to between waves.

Gambler - A Gambler could find a gamebreaking spell combo, or could be a complete dud, but there's no way to find out which without a more reliable buddy to keep them alive through the early game.

https://gtm.steamproxy.vip/ugc/2485493794730193217/CE9966A61ADBC3FE21A73AC0B1A666BA49ED2F96/?imw=256&&ima=fit&impolicy=Letterbox&imcolor=%23000000&letterbox=false

If this screenshot didn't make it obvious already, I'm still a newbie. I've tried to stick to verifiable facts and avoid making assumptions, but I've likely made some mistakes. Feel free to comment below.