In some fanfictions, Snape has badass moments when he outsmarts Voldemort. For example, he manages to mislead Voldemort about the location of a crucial magical artifact. He uses his Occlumency skills to his advantage, hiding his true thoughts and intentions while presenting false information in a very clever way. This not only shows his intelligence but also his courage as he risks his life to deceive the Dark Lord.
One badass moment could be when Ezra single - handedly takes on a group of stormtroopers in a narrow corridor. Using his lightsaber and the Force to deflect blaster bolts back at them, he cuts through their ranks like a hot knife through butter. Another might be when he uses his Force powers to manipulate a large ship's controls from a distance to prevent it from crashing into a rebel base.
In these fics, Sakura often becomes badass through intense training. She realizes that she needs to be stronger to change things in Konoha or to prove herself. For example, she might train under a mysterious master or in isolation, like in 'Sakura's Solitary Training' where she spends months alone in the forest, honing her skills.
Well, it could be characters like Draco Malfoy. In the original series, he had his moments of growth and in fanfics, he might be one of the main Slytherins to defend Hogwarts. Maybe he finally realizes the importance of the school and his own values change. He could be joined by other Slytherins who were perhaps overlooked in the official story but show their true courage in the fanfic.
His unwavering determination is another factor. No matter how tough the situation is, Adrien in fanfictions doesn't give up. He is willing to risk everything to protect the people he loves and the city he lives in. This strong will and selfless attitude are what make him a truly badass character in many fanfictions.
I'm not sure which anime you're referring to. If you can provide more information such as characters, background, or title, I will try my best to provide you with a more accurate answer.