Your classes determine your features, spells, starting equipment, and all the other gameplay mechanics. To mimic the Dragon Age system, the base 5E classes have been categorized into three categories. Each of these three categories comprises six individual classes, making for eighteen in total. Thus, these fulfill the role that subclasses do in vanilla, except in this case standing in for the class specializations present in the video games.
The warriors of Thedas are many and varied, serving as both front-line tanks and damage dealers. The Champion is the elegant and streamlined inheritor of the vanilla Fighter class, but themed around knighthood and chivalry. The Sellsword is an expert manipulator of the battlefield, borrowing from the Battle Master specialization. The Templar is the Theodosian version of the Paladin, specialized as an anti-magic tank while carrying with it an entirely new set of mechanics based around the empowering and addictive nature of lyrium.
The Magekiller is an interpretation of the Templar from a Tevinter perspective, drawing inspiration from Fenris’ abilities from Dragon Age 2. The Berserker is the Barbarian of Thedas, inheriting the warrior culture of the dwarves, while the Katari does much the same, but for the shock troopers of the Qun.
Champion
Sellsword
Templar
Magekiller
Berserker
Katari
Reaver
Spirit Warrior
Clever, tricksy, and supremely useful and versatile, the Rogue Classes encompass the full range of damage dealers and debuffing supports from the games. The Assassins are pure DPS, geared around stealth and sneak attack damage. The Duelist takes a more direct approach, borrowing from the Swashbuckler subclass to specialize in one-on-one encounters. The Bard is a notable departure from the vanilla class, as it does not possess magic (which is significantly rarer in Thedas) instead preferring the intrigue and espionage of the Orlesian tradition. The Lay Sister is the Andrastian application of the bardic arts, acting as an agent of the Chantry with a toolset built to support as well as disrupt.
The Ranger brings a level-scaling Animal Companion to the table, borrowing off the fixed and empowered version of the Ranger from the Unearthed Arcana of D&D 5E. Lastly, the Artificer is a notable departure from the class sharing the same name--the Theodosian Artificer being a rogue in the style of Varric Tethras, based around traps, ranged weaponry, and dirty but practical tinkering rather than high-minded academic engineering.
Assassin
Duelist
Bard
Lay Sister
Ranger
Artificer
Tempest
Mage Classes
Mages are incredibly powerful and universally feared in Thedas, as magic in this world carries a much higher inherent cost than in vanilla D&D. Thus, the Mage Classes are all notably different from their vanilla counterparts, partly due to the change in the nature of magic between settings. In Thedas, all magic comes from the Fade, and thus requires no material components. Instead, magic carries the cost of exposure to spirits and corrupting influences. The Spirit Healer functions off of this spiritual connection, being a powerful spellcaster and healing support. The Keeper takes the transformation abilities of the Shapechanger specialization and the Druid class to become a nature-based mage capable of tanking while Shapechanged. The Magister is the traditional academic wizard, whose greatest strength is its versatility and incredibly wide toolset.
The Runesmith offers permanent (if expensive) upgrade mechanics, enabling the magicless dwarves to wield powerful forces via careful application of lyrium and enchantment. The Blood Mage is a very tanky but high-risk class, with far more health than any other spellcaster, with the costs of only healing by killing enemies and constantly running the risk of demonic influence, as determined by the brand new Temptation mechanic. The Saarebas are built off of the Wild Magic Sorceror, as befits the untrained and instinctual mages of the Qun.
Spirit Healer
Keeper
Magister
Runesmith
Blood Mage
Saarebas