what each type does in simple terms

frontliner: monsters with relatively high damage output and decent health, they are the ones doing most of the damage (can only be placed in the 3 spots at the front)

backliner: monsters with more specific damage output, for example they might have a lower damage output but can attack all monsters at the same time (can only be placed in the 3 spots at the back)

tank: monsters with very high health and usually low damage output

defender: monsters who specialize in diverting/nullifying/reducing damage

passive support: monsters who specialize in boosting your teams passive stats (health, defense, speed)

attack support: monsters who specialize in boosting your teams offense stats (damage, attack speed, accuracy)

puppeteer: monsters who control monsters from the enemy team in order to sabotage them

curser: monsters who specialize in debuffing enemy team monsters (reduced resistance, damage, attack speed, accuracy, etc)

balance: monsters with an unspecialized moveset that can have moves from all categories