It could be an ancient and powerful wizard. Maybe the wizard sees potential in Beast Boy and decides to grant him new powers to help him in his fight against evil.
Well, he might become even more powerful and be able to transform into new and amazing creatures. Maybe he could gain the ability to fly in his animal forms, which would be really cool.
He might gain the power of enhanced healing. So not only can he transform into different animals, but if he gets injured during a fight or accident, he can heal himself much faster than before. This would make him even more of a formidable hero in the fanfic's story line.
His friends might be in awe of him at first. They would see him as even more powerful and might rely on him more during battles. For example, if he has new powers like controlling the elements, they could use his abilities to their advantage in strategic ways.
Perhaps he gets a power related to mind control. This would allow him to influence the actions of his enemies or even make them fight among themselves. He could also gain a power that lets him absorb the powers of his defeated foes. So, every time he defeats an enemy, he becomes stronger by adding their powers to his own arsenal.
Maybe a girl with a similar power. For example, a girl who can communicate with animals telepathically. They would have a deep understanding of each other because of their shared connection to the animal world. They could go on adventures together, using their powers to help animals in trouble. Their relationship would be based on mutual respect for their powers and a shared passion for animals.
There could be. Fanfiction is a vast world, and fans often come up with unique and sometimes unexpected storylines. Beast Boy and Starfire are both popular characters, so it's not unlikely that someone has written a fanfiction with this plot. But it might be hard to find among the countless other fanfictions.
One possible new power could be the ability to control electricity. He could use it to stun enemies, power up machinery, or even create electromagnetic fields to deflect attacks. This would add a whole new dimension to his combat style and problem - solving skills.
In the fanfiction, perhaps Beast Boy's girlfriend could be a new superhero in town. They meet during a battle against a common enemy. She first sees his brave side when he's in the form of a fierce beast, and she's drawn to him. As they get to know each other more, they start to date. Their relationship could be filled with adventures as they fight crime together and also deal with the normal relationship stuff like jealousy and misunderstandings.
His new powers might make some of his friends a bit wary at first. They could be worried that he's changing too much. But as they see him use his powers for good, they'll likely become more accepting. His enemies, on the other hand, will be more afraid of him and might target him even more.