Weather Mage: As the name implies, they can manipulate the weather, affecting enemies within a certain radius. They gain more weather spells by leveling up. Examples for their spells are Wind, which slows down fliers immensely, various debuffs like heat or cold, and various kinds of storms after promotion, which serve to attack enemies directly. They can use Anima and promote into Meteorologists. They are of immune to natural weather effects (like being slowed down by rain and having a wide range of vision in FoW), but can be harmed by the enemy´s weather spells.
Lizard Rider: Similar stats as Wyvern Riders. They have less movement than Cavaliers, but don´t get slowed down by terrain as much. They are weak to horse- and wyvernslaying weapons. They wield lances and get access to axes after promotion to Lizard Knight.
Blood Mage: They sacrifice HP for spells, FE2-Style. Less overall attack power than normal mages, but their variety of spells gives them much utility.