Character class

A Character class is a gameplay-based method many RPGs use to arbitrate the capabilities of playable characters. In Golden Sun and Golden Sun: The Lost Age, character classes serve just this purpose, dictating enhancements to characters' base statistics and what arrangements and elements of Psynergy they may use.

Unlike many RPGs, such as Final Fantasy, characters in Golden Sun games do not specifically select classes to pursue and develop abilities in; Classes are merely "settings" that can be instantly changed anytime based on what their level of skill in a particular element is. This is determined both by their own innate element, as well as how many and what elements of Djinn are Set onto each character.

Classes serve several important roles from a gameplay perspective. Firstly, they add a great deal of diversity to the game, opening up a large number of Psynergy and statistical (and hence strategic) combinations. Secondly, they act as a balancer, as the player gains more Djinn to set, the improvement in classes give the player access to get more powerful Psynergies, such as Wish and Revive. This both serves as an incentive for the player to collect Djinn (and hence complete the associated optional, but more complex, puzzles) and acting to stop the player gaining spells that are too powerful too early on. Because of this, the player's selection of classes can aversely change the outcome of a battle. This is most evident when the Monster Skill Djinn Storm is used on the player. The removal of all Djinn cripples an otherwise strong party by reverting the Adepts to their default classes, which serves to make the battle much more challenging. By extension, this is also a feature that balances the powerful summon sequences, as putting a Djinni on Standyby stops it from influencing an Adept's class, hence weakening the party, which in turns creates a tactical dilemma that forces the player to think more carefully about their actions.

"Trees"
There are four "trees" of classes: Mono-Element, Duel-Element, Tri-Element and Item Dependent (The Lost Age only). The "number" of elements includes the elements of Djinn set to the Adept, as well as the Adept's base element. For example, the tri-elemental Ninja class series for Isaac requires Jupiter and Mars Djinn, but also includes his natural Venus element, thus it is considered "Tri-Elemental".

Mono-Element
The Mono-Element classes (also called the "Default" classes) involve having only one element of Djinn to a particular Adept and that element is the element the Adept is aligned with (Water for Mia and Piers, Fire for Garet and Jenna, etc.) and all through the progression of the class, only one type of Element is needed. The classes stem from the base class of the character (EG: Felix and Isaac being Squires follow the Squire class tree.)

Pros of the Mono-Element Classes

 * Simple, straight-forward and easy. Sticking to the Mono-Element classes will get the job done without much fanfare.
 * Using Djinn and summons in battle do not carry the potential of crippling an Adept with an undesired, and perhaps dangerous, class switch.
 * Because only one element of Djinn is required for any given Adept, the elemental power (+5 Power per Djinni set) of that single element is going to be higher than that of other classes, which when augmented by the Adept's naturally higher power (Felix's and Isaac's Venus power, Jenna's and Garet's Mars power, etc.) is very potent.

Cons of the Mono-Element Classes

 * Each one has one or two painful shortcomings, such as terrible stats in one area, (for example, the Guard class series has the worst agility of all the classes, and the second worst PP stat (this is only compounded with expensive Psynergies like Volcano and Liquifier), while the Water Seer class series has lackluster agility and a bad offensive Psynergy lineup).
 * Each class has only a single element worth of Psynergy, which can prove annoying when facing enemies who have a high resistance to that particular element.
 * A few quick Djinn trades into the Duel-Element classes can quickly patch up these shortcomings.
 * Small array of Psynergy at your disposal.

Duel-Element
The Duel-Element classes require having a majority of Djinn from another element, and one or two Djinn of the Adept's own element for the higher levels.

Pros of the Duel-Element Classes

 * Fairly easy and straightforward, though not as much as the Mono-Element classes.
 * Quite often they will patch up the shortcomings of the Mono-Elements with an improvement to the Mono-Element's strengths with very little sacrificed (IE: Mia to a Hermit).
 * Adepts have two elements of Psynergy in their arsenals, allowing them more flexibility against monsters with a high resistance to one element.

Cons of the Duel-Element Classes

 * Some care must be taken when using Djinn and summons so as to not accidentally shift the Adept into an entirely different class tree.
 * Some care must be taken when selecting duel-elemental classes that you don't exasperate an already painful shortcoming (Isaac, Felix and Garet to a Brute)
 * A look at the Tri-Element classes might be more than enough to skip this tree altogether.

Tri-Element
The Tri-Element classes require two different types of Djinn attached to the Adept.

Pros of the Tri-Element Classes

 * Statistically, the Tri-Element classes are the best, and any shortcomings they might have can easily be compensated for by their other stats (such as the Ninja class series's sub-par defense being compensated for with the highest Agility and second highest attack).
 * Three elements worth of Psynergy in the Adept's arsenal allows for great flexibility against monsters.
 * Tri-Element class possess some hard hitting Psynergies and quite often have a PP pool to run with it (such as Quick Strike in the Samurai class series, and the Thunderclap Psynergy series in the Ninja class series).
 * Despite the challenge of setting and unleashing Djinn while avoiding unwanted class shifts, with the Djinn so spread out, summons can be churned out in fewer turns than say everyone in their mono-element classes. Example: Issac is a Ninja (3 Jupiter, 3 Mars Djinn), Garet is a Dragoon (3 Mercury, 3 Venus) and Ivan is a Ranger (3 Mercury, 3 Mars). On the first turn, Isaac and Ivan both set one of their Mars Djinn. On the second turn, Isaac and Ivan both set another Mars Djinn, and with Garet being a Dragoon (bad Agility) he can then summon Meteor in that same second turn, as he will probably take his turn last, thus pulling the summon off in two turns (compared to 5 if he was his Mono-Elemental class).

Cons of the Tri-Element Classes

 * The Tri-Element classes are tactically challenging and great care must be taken when using Djinn in battle to avoid an unwanted class change (an all out summon rush is probably going to end in disaster for the Adepts).
 * Djinn Storm might be more of a death sentence than it already is, especially if your handling the fight with limited summons, as on their own, the Tri-Elemental classes pack a hard punch.
 * Six or seven Djinn are required to get the first tier of the classes, making them unavailable until the later parts of the games.

Item-Dependent
The item dependent classes require the item that grants the class to be equipped (Trainer's Whip for Tamer class series, Mysterious Card for Pierrot class series and Tomegathericon for Dark Mage class series) and 1, 2, or 3 (for the 2nd, 3rd and 4th levels) Djinn of each Element that is NOT the Adept's base element.

Pros of the Item-Dependent Classes

 * Possess psynergy from each element allowing unparalleled flexibility.
 * Possess psynergies that are unique to each class.
 * Statistically sound, strengths make up for weaknesses (the Tamer's dismal PP pool is offset by its incredible attack, and the fact that most of its Psynergies draw on the attack stat when calculating damage).
 * Even with all Djinn on standby or recovering, the Adept maintains the first tier of the class (EG: Isaac, equipped with the Mysterious Card, would revert to a Pierrot and not a Squire when all of his Djinn are on standby or recovering).
 * When unleashing Djinn, it's fairly easy to maintain the class of the Adept in question.

Cons of the Item-Dependent Classes

 * Only one of each may be present at any time.
 * Requires three elements worth of Djinn.
 * The item required for the class must be found first.

Side Note
One thing to take note of with the Item Dependent classes it that they require three elements worth of Djinn to progress. Even with all 72 Djinn, 8 Adepts, and 3 items, it's still going to leave an awkward amount of Djinn floating around. Normally, when you're trading Djinn around into Duel and/or Tri elemental classes, you have enough Djinn floating around to get everyone to the top level tiers of the classes. When dealing with the Item-Dependent classes, at least one Adept is going to get a little shafted.

When Trading
When trading Djinn around to change classes, it's generally best to pick one tree for one set (One Venus, one Mars, one Jupiter and one Mercury) of Adepts. For example, have Isaac, Garet, Ivan and Mia in Tri-Elemental classes while having Felix, Jenna, Sheba and Piers in Duel-Elemental classes, or both in Tri, or both in Duel.

Which to choose?
The classes that you pick for your team of Adepts are based entirely on your personal likes, dislikes, goals, objectives, feelings and preferences. Do you think Jenna seems more "Ninja-ish" than "Samurai-ish"? Or do you think she seems more "Page-ish"? Experiment a bit and see what strikes your fancy.

List of top-level classes
Below is a sortable table of each class series' most developed stage as of Golden Sun: The Lost Age, including the average of all six of their statistics, the average of their statistics when Luck is taken out of the equation, and the average of their statistics when both Luck and PP are taken out of the equation.