Who could be the main antagonist in 'Obito x Kakashi time travel fanfiction'?

One common theme is redemption. Since they both have a lot of regrets in their original timeline, time travel gives them a chance to fix things, like saving their friends or preventing the destruction of the village.

One idea could be that Obito and Kakashi are sent back to their childhood days. Obito then tries to prevent certain tragedies that happened in their past, like the death of his comrades. He might also try to change Kakashi's cold - hearted nature that developed over time. This could lead to a whole new set of relationships and events in the Naruto world.

It could be a time - traveling villain who is trying to disrupt the timeline for their own gain. This villain might be trying to erase certain events or people from history to change the future in a way that benefits them.

It could be a time - traveling sorcerer who wants to change history for his own evil purposes and sees Achilles as a threat. The sorcerer might try to stop Achilles from getting back to his own time or use his knowledge of the future to his advantage against Achilles.

A time - traveling bounty hunter could be the main antagonist. He might be after Lucy because she has somehow disrupted the time - space continuum. He's cold - hearted and will stop at nothing to bring her to some time - traveling justice.

Perhaps an ancient evil that was sealed away long ago but is released due to Temari's time - traveling disruptions. This evil entity then starts causing chaos in the past, and Temari is the only one who can stop it with her modern skills and knowledge.

It could be a time - traveling villain from the future who wants to change the past to gain more power in their own time. They might try to stop Naruino from achieving their time - travel goals.

There's also 'Time's Redemption'. This fanfiction has a unique take on time travel. Kakashi and Obito are sent back together. They have to work together to change the fate of the Hidden Leaf. The story delves deep into their relationship, exploring how they understand each other better through this time - traveling adventure.

One idea could be that Kakashi travels back to the moment right before Obito's 'death'. He uses his knowledge of future events to prevent the cave from collapsing on Obito. Then, together they are able to rescue Rin more effectively and change the whole tragic course of events.

Perhaps an old enemy of Naruto's who resurfaces and decides to target his family. This could be someone who was defeated by Naruto long ago but has now grown stronger and wants to cause harm to his loved ones. They might also see Kakashi as a threat in protecting the family.