El débil con sangre de rey dragón

For fifteen years, duke's second son Dorian is mocked as nearly powerless by stepmother Morgana and brother Roland. In truth, his ancient dragon-king blood has awakened and he is the only divine-tier mage in three centuries. Forced to enter the imperial competition for Princess Isolde's hand as an apparent weakling, he gradually reveals his strength through magical tournaments and ruin trials and proves that Morgana poisoned his mother.