Others Awaken SSS-Rank Classes, I Summon Calamities

When others awakened shining SSS-rank classes, Arthur awakened a variant of the summoner's class Calamity Summonera class deemed useless by the world due to its unknown potential.Three years passed. No level ups. No hope. No future.Being stuck at the same level for a long time, he had lost hope in his talent.Then came the day he was thrown into an E-rank dungeon and doomed to die, Arthur decided to fight with his life on the line.Fortunately, after managing to kill a few beasts, he obtained a core that activated his unique classCalamity Summoner.[Congratulations on activating the Calamity Summoner's class.][Note: Calamities are beings from countless eras who have been hunted and killed due to their potential being too terrifying for the world to withstand.][Congratulations on summoning the Dragon Knight as your first Calamity!]On the verge of death, Arthur could only stare at the massive being radiating oppressive might and plead as he lost consciousness."Save me my summon."Time passed, and Arthur gradually realized a terrifying facthis summoning ability isn't supposed to exist.After all, if even the so-called gods were willing to let humans possess SSS-rank abilities then what kind of power could one hold that would drive the gods themselves to wipe it out?