All of the core PHB classes exist in Tarab, with few mechanical alterations and a few flavor ones.
Barbarian- Usually coming from the tribal regions of Tarkut and the mountains marking Tarab’s northernmost borders, Barbarians are the product of merging mysticism and warrior training. Through years of meditation, trance, and the habitual consumption of certain plants and herbs, barbarians have learned to culture within themselves a powerful well of emotional and spiritual energy which allows them to enter fits of rage and perform superhuman feats.
Bard- Bards hold a special place in Tarab, being seen as preservers of culture, history, and lore. The magical effects of bardic music is also well documented, and has been studied and classified as Inspired Magic by scholars; though it is generally not as powerful as Wizard magic, it does not drain the mana from the land around it, instead using sympathetic actions to create effects.
Cleric- Clerics are quite common, though most of them tend to be cloistered, and adventuring clerics are rare indeed, typically coming from the ranks of young idealists who believe they can learn more from travel and experience than scholarly books and theological debate.
Druid- Followers of the Old Ways, Druids are voluntary exiles from civilization at best, hunted pariahs at worst. Devoted to gods and spiritual ideas long since fallen into obscurity, they run the risk of being condemned as heretics should their allegiances become common knowledge.
Fighter- Warriors of all backgrounds can be found in Tarab. Most trained Tarabic fighters favor curved blades, especially the scimitar, and lighter armor that can be quickly donned and removed in the desert heat. The influence of the Crusaders has lead to a cross-fertilization of metallurgical sciences, and heavier straight blades, axes, polearms, and composite plate and scale type armors have become commonplace in major urban areas along the coastlines, where the climate is more forgiving and local travel is far more expedient. The Mamluk armies of Pheogypta are renowned exemplars of the Tarabic warrior tradition.
Monk- Isolated communities of monks exist scattered across Tarab, typically near one of the three Holy Cities. These ascetics are often closely associated with Mysticism, though it has been heard of on occasion that a traveling master takes up a poor urban youth and trains them in secret arts of combat. It is rumored that the Injiltians have similar secret brotherhoods of monks who train on islands in the Middle Sea.
Paladin- Paladins are more common in urban areas, as religious study is as key to their lifestyle as martial training. With the lack of a formal church hierarchy to follow, many paladins travel on their own, or form groups that are dedicated to the defense of the faithful on the borderlands.
Ranger- Often the descendants of Bedouin who bridge the gap between civilized and nomadic life, rangers are the explorers and guides who tread where others fear to, and see things that most would not believe. Rangers carry with them a level of respect for their skills and likely Bedouin heritage, but they rarely operate in any organized manner.
Rogue- Rogues, rebels and thieves are the subject of a bizarre double standard in Tarab- while they feature as the heroes of many popular stories and poems, their notoriety rarely translates to public support if caught.
Sorcerer- Only two known sorcerers exist in the world- the Oracle and the Magister, both of whom are important figures in Tarab politics and culture.
Wizard- Gathering in highly regimented fraternal organizations, Wizards eschew a normal life for scientific and arcane study. All wizards defer to the will of the Magister- those who do not do so, or who willfully abuse their power, seldom live long enough to regret it.