Aberforth Dumbledore can be a very important character in these fanfictions. He is Albus Dumbledore's brother and has his own feelings and history related to his brother and Grindelwald. He might be the one who tries to bring his brother back from the brink when Dumbledore is too involved with Grindelwald. Also, Leta Lestrange could be popular. Her family's dark reputation and her own complex relationship with Newt and the wizarding world in general can add an extra layer of drama to the fanfictions involving Dumbledore and Grindelwald.
Well, it could be that Dumbledore has some sort of hidden device or spell that he activates when kidnapped. For example, he could have a charmed object that sends a signal to his allies, like the Order of the Phoenix. His allies then come to his rescue and he manages to escape during the chaos. Also, Dumbledore is extremely intelligent. He might outwit Grindelwald by engaging him in a complex conversation full of riddles and misdirections, which gives him an opportunity to break free.
I really like 'Shadows of the Past'. This fanfic explores the emotional turmoil that Dumbledore must have felt when facing Grindelwald. It's well - written, with vivid descriptions that make you feel as if you're right there in the wizarding world with them.
One common theme is the struggle between good and evil. Their relationship is at the center of this, as Dumbledore represents good and Grindelwald represents a more complex form of evil. Another theme is the power of friendship and how it can turn sour.
One interesting aspect of Albus Dumbledore x Gellert Grindelwald fanfiction is the exploration of their complex relationship. Their early friendship and how it devolved into enmity due to their different views on magic and power is a common theme. Fanfiction often delves deep into their shared past, like their time in Godric's Hollow, and how their bond was initially one of mutual admiration and a shared vision for a new wizarding world order. It also shows how Dumbledore's love for Grindelwald, whether platonic or more, conflicted with his sense of right and wrong.
One interesting plotline could be exploring their early days at Hogwarts together. Maybe they were both brilliant students with different outlooks that gradually diverged. Another could be a story where they meet again after Dumbledore defeats Grindelwald, and there are still unresolved feelings and thoughts between them. A third one might be a fanfiction that delves into an alternate universe where they actually work together to achieve some 'greater good' that they both misinterpreted in different ways.
The theme of forbidden love is quite prevalent. Their relationship was not straightforward in the original story, and in fanfiction, it's often explored as something that is not easily accepted by the wizarding society. Also, the theme of sacrifice. They might have to sacrifice their love for the safety of others or for a greater cause. In some fanfictions, their love is also about self - discovery. As they get closer, they learn more about themselves and their own values.
One possible motive could be jealousy. Grindelwald might be jealous of Dumbledore's power and popularity in the wizarding world. By kidnapping him, he wants to prove that he is the more powerful one.
A popular theme is the exploration of their youth and the dreams they shared. It shows how they were once two idealistic young wizards with big plans for the wizarding world. Another theme is the power struggle within their relationship. As Grindelwald became more power - hungry, it created a rift. And of course, the theme of love and betrayal is often present, as Dumbledore had to ultimately turn against the man he once cared for deeply.