It could be another powerful mage who is jealous of the scorpion mage's growing power. This mage might see the scorpion mage as a threat to his own dominance in the magical realm and would do anything to stop his rise.
It could be about the scorpion mage's origin story. Maybe he was an ordinary person who got cursed and turned into a scorpion mage. Then he had to learn to control his new powers and face many challenges in a magical world.
A powerful sorcerer who has been consumed by despair could be the main antagonist. This sorcerer might see the mage of hope as a threat to his plan of spreading darkness and hopelessness across the world.
It could be a super intelligent pirate who has been secretly controlling events in the One Piece world. This antagonist might be several steps ahead of everyone, creating elaborate plans to take over the Grand Line. Luffy, with his newfound intelligence, has to match wits with this foe.
The main antagonist could be a mean-spirited mole. This mole is constantly digging tunnels under the garden and causing chaos. He doesn't like Gnomeo and Juliet's love because he believes it's disrupting the natural order of the garden. He tries to separate them by causing misunderstandings between their families.
An organization that believes in using Pokemon for dark magic could be the main bad guy. They see Iris and her Pokemon as a threat to their plans, so they constantly try to stop her. They might have their own powerful, corrupted Pokemon that they use to battle Iris. They could also be stealing Pokemon from other trainers to use in their dark experiments.
It could be a rival politician who sees Trump's association with Grimace as a threat. This rival might try to spread false rumors about Grimace being a dangerous or untrustworthy being, just to undermine Trump.
It could be a powerful and corrupt businessman. He saw the potential of the zombie virus for his own gain, like using the zombies as a weapon or slave labor. So he tries to stop Rizzoli and Isles from interfering with his plans.
In some cases, it could be the Ministry of Magic itself. If Severus's schemes involve going against the established rules and power structures of the wizarding world, the Ministry might see him as a threat and act as the antagonist. They could try to stop his plans, leading to a conflict between Severus and the Ministry.
It could be an older, more experienced thief who sees the Artful Dodger as a threat. This thief might want to eliminate him to keep his own territory and reputation in the criminal underworld. He would be constantly trying to thwart the Artful Dodger's escape plans and set traps for him.
It could be a jealous rival artist. This rival might feel that Alan Davie has always overshadowed them in the art world. So, they decide to kidnap him to stop him from creating more masterpieces and taking all the limelight.