YMMV / Riordanverse

• Complete Monster:
  • The Serpent's Shadow & Demigods & Magicians: Setne, son of Pharaoh Ramses the Great, was a murderer and blasphemer who escaped oblivion to return to Earth and sow chaos, being responsible for massive amounts of destruction, including The French Revolution and World War I. While initially assisting the Kane siblings against Apophis, Setne betrays them to instead try to seize control of the great serpent, intending on feeding it many souls in the afterlife, his father included, before unleashing Apophis to destroy most of the world whereupon he will proceed to rule the rest. Upon failing in this, Setne later returns to attempt to devour the gods of every pantheon to make himself the supreme one god who will dominate the entire world.
  • The Sword of Summer:
    • Surt, lord of the Fire Giants who also appears in 9 from the Nine Worlds' "I Play with Fire", seeks to bathe the entirety of the Nine Realms in flames and despises the god Frey for his compassionate, healing nature. Previously responsible for the Great Chicago Fire, Surt causes explosions throughout Boston as he hunts Magnus, threatening to incinerate nearby civilians if he isn't given the Sword of Summer and eventually killing the demigod with molten asphalt. Despite being weakened by their fight, Surt confronts Magnus and his friends again on the island of Lyngvi, slaying the Valkyrie Gunilla and attempting to claim the sword once more so he can free Fenris Wolf, start Ragnarok, and finally kill Frey before burning down all of existence.
    • Fenris Wolf, the monstrous son of Loki, was forced to be restrained by the Aesir due to the danger presented by his savage nature. Managing to loosen his bonds over the years, the Wolf causes havoc throughout the Nine Realms using his far-reaching Compelling Voice, manipulating events to secure his freedom. When confronted, Fenris Wolf gloats that he had Magnus's mother killed so he would become strong enough to retrieve the Sword of Summer—additionally noting that he ate Blitzen's father and countless other adventurers—in an effort to enrage the group so they will come closer to his confined circle and be devoured. Acting as the mastermind behind Surt's plan to claim the Sword of Summer, Fenris Wolf hopes for the blade to be used to cut away his remaining bonds, despite knowing full well that his release will usher in Ragnarok.
  • The Trials of Apollo: Nero, aka "The Beast", is an infamous Roman emperor and one of the three leaders of Triumvirate Holdings. Having helped Kronos and Gaea with their attempts to end the world by supplying their forcers with equipment, Nero strikes a deal with Python to find the Grove of Dodona, and to this end has his adopted daughter Meg spy on Apollo. Having killed Meg's birth father, Nero regularly abuses Meg to keep her in line. In his attempt to find the Grove, Nero has a group of Demigods kidnapped, threatening to burn them alive, before attempting to have the Colossus Nerosis destroy Camp Half-Blood. Nero later has his adopted Demigods attempt to burn New York to the ground and, when one of his allies Lu betrays him, Nero has her hands cut off, making Meg think it was her fault. Later attempting to have Meg use Sassanid Gas to kill the heroes at the threat of killing Apollo, Nero orders his minions to kill her when she refuses.

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