In Saga Frontier, there are 5 different races in the world. You will eventually have to use all of them, if you plan on playing all 7 scenarios. All of them are unique in the way of using equipment, leveling up and gaining abilities. Here are some explanations on all of the races:

Human-The common race of characters. Humans gain status points in certain categories by fighting fights. Certain status categories might go up as a result of that character's battle actions or by method of attack (Swords, Guns, Fists, and Magic), however; it is random in almost all cases. Humans can equip any weapon or item, however, they can only hold 4 at once (NOT as in 4 weapons and items; but there are 4 "shared" spaces for weapons and items). They can also have 4 spaces for any kind of armor you choose; however, they cannot equip more than one specific type of armor, except for Accessories. If Suits are worn by Humans, then Armor, Helmets, and Boots cannot be equipped. Humans are proficient (by proficient I mean able to learn Techniques) in using all types of weapons and magic (though they are unable to learn Mystic Magic). They have 8 spaces for abilities, and thus, only 8 abilities can be equipped at once. They will learn Sword and Fist techniques in battle. Because they are learned in battle, there must be a space open in their abilities list in order to learn a Sword/Fist Technique. Some Techniques can only be learned/used using certain Swords called "Katanas". Gun Techniques and Magic Techniques are learned after battles, if learned at all (You will be notified as that person is gaining experience for the fight if a Gun/Magic Technique was learned). With this in mind, you do not have to have an empty space in you abilities list to learn a Gun/Magic Tech, as they will go to your unused abilities folder. And also, certain statistics are raised more by certain methods of attacks (Ex. You will never gain any intelligence points using Swords, and very little using Fists). Lastly, Humans can Learn Dodge Techs, which, when learned, always evade a certain type of attack. Dodge Techs require an empty spot in your equipped abilities list.

Mecs-Robots, essentially. Mecs have 8 spaces to equip anything you so desire, and they gain status points through equipment, so the stronger the equipment, the better the Mec will be. Guns and Suits raise status points the most. Mecs can use Guns, Fists, and Swords, but are not proficient with them. Mecs learn Techs (I made a rhyme!) by absorbing them from enemy Mecs. For example…Pretend we are using the main character Mec--T260G is his name-and we just finished a battle against an enemy Mec-We'll use MecGod as an example. While everyone is gaining experience, eventually T260G will be given the option to absorb an ability from MecGod. If you do, you have a chance at learning an ability called "Tiger Program". This is a first come, first serve thing; for example, if you have 2 Mecs in your group-the second one will be Zeke for this example-and T260G gets the option to absorb the ability first, and you want Zeke to learn the ability, you will have to choose not to absorb it with T260G, so that Zeke will have a chance to absorb it. Note that not every Mec can learn every ability, though. The amount of abilities they can hold at once depends on the strength of their Gun; bigger/more Guns = more Abilities. Lastly, certain Mec "Types" have built-in Abilities, which can be sealed as well.

Monsters-The inferior race (I think so). Monsters learn abilities by absorbing them from monsters. As with Mecs, it is a first come, first serve thing, so if you want monster # 2 to absorb that Ogre, then have monster # 1 skip it or absorb some other monster. They gain status points by absorbing different monsters. The stronger the monster, the better the status. The trick is to find a well-rounded monster to make the character useful. They also gain status points by absorbing different monsters, because doing so will often change them into a different monster. The stronger the monster is, the better the status of the monster will be. The trick is to find a well-rounded monster to make the character useful. Monsters gain 4 HP for every Ability they absorb, regardless of what monster you are (pretend you were an Ogre with 192 HP, then you absorbed some new Ability and became a different monster; if you were still an Ogre, you would have 196 HP). Monsters cannot use any sort of attack besides Fists and Monster Abilities, and they are not proficient with fists. Monsters only have four spaces for equipment, and they can only equip Accessories. The best thing to do is equip them with Accessories that compensate for the weaknesses in their status (A blatant observation, but the fact holds true even more so with Monsters, due to their limits).

Mystics-Somewhat a hybrid of humans and monsters. Mystics gain status points in certain categories by fighting fights. It is random, like the way that Humans gain Status points, however, Mystics will only gain HP, WP, JP, and Charm in this manner; All other Status points are gained by absorbing monsters with Mystic Weapons (More details below). Mystics, like Humans have four spaces for Weapons and Items, and four spaces for all types of Armor, however Mystics have a specific Weapon or Armor that cannot be unequipped, so you will have one space in one of either Weapons or Armor occupied (The equipment varies by the character). Mystics can use all Weapons; however, they are not proficient with any Weapon. Mystics have 3 special Weapons: Mystic Sword, Mystic Glove, and Mystic Boots. These three Weapons (I will refer to them as Mystic Weapons from now on) can be used to absorb monsters during the fight, and with it will come an Ability. The Abilities vary by the monster AND the Mystic Weapon, and only one Ability can be carried on each Mystic Weapon. Mystics are proficient with Magic, and always have Mystic Magic mastered already. However, Mystics are incapable of learning Realm Magic. And also, Mystics cannot learn Dodge Techs (not a big loss).

Half-Mystics-There is only one Half-Mystic in the game, unfortunately; Half-Mystics (Or Half-Mystic, I should say) have the good properties of Humans and Mystics. Half-Mystics gain Status points the same way as Humans and Mystics do (She gains all different Status points through battle AND through Mystic Weapons!). Their equipment management is more like Humans (No mandatory equipment! Whoopie!). Half-Mystics are proficient with all Weapons and Magic (except Realm Magic), not to mention that they (she) can use Mystic Weapons. They way that Half-Mystics learn Techs for Weapons is the same as Humans, and the way they learn Mystic Weapon Abilities is the same as Mystics (These should have been obvious though), the same goes with learning Magic. And Half Mystics can use Dodge Techs.

Anything I said incorrect (Probably, haha)? Did I totally forget something? Please tell me.