Often, a plot device could be a mission given to Oliver in the past. For instance, he is tasked with saving a village from a plague or preventing a war. This gives his time - travel a purpose. Another is the use of time - loops. Oliver might find himself stuck in a repeating day in the past and has to figure out how to break the loop. Additionally, the concept of anachronisms can be a plot device. He might introduce something from his time into the past, like modern technology, which then has unforeseen consequences.
A typical plot device is the discovery of a time - key object. In Oliver goes back in time fanfiction, this object could be a magical amulet or an old - fashioned watch that allows him to travel through time. This gives a clear reason for his time - traveling. Another plot device is facing a villain from the past. Oliver may have to outwit a powerful historical villain who is causing chaos in that era. And cultural shock can be a plot device too. When Oliver arrives in the past, he has to adapt to the different customs, languages and social norms, which can lead to some humorous or tense situations.
One possible plot twist could be that Oliver goes back in time and accidentally changes something that makes his friends turn into enemies in the present. For example, he might prevent an event that was crucial for the formation of their friendships. Another could be that he meets a younger version of himself and has to convince that version to make different choices without revealing too much about the future. It could also be interesting if he goes back to a time when his city was in a different state, like before the rise of a major villain, and he has to stop that villain from ever emerging in the first place.
Oliver can start by learning the language of the time. If he goes back to a different era, say the Middle Ages, understanding the local language would be crucial for communication. He could also study the social norms. For example, if he's in a very hierarchical society, knowing how to behave around different classes is important. Another way is to get used to the different living conditions. If there are no modern conveniences like electricity, he has to learn to do things the old - fashioned way.
Often, the 'fish out of water' feeling is a plot device. Caroline, coming from a different time, would be out of place in the past. This can lead to humorous situations as well as moments of self - discovery. Another one is the time - travel mechanism itself. It could be a magical object like a time - traveling amulet that has its own rules and limitations. She has to figure out how to use it properly to get back to her own time. And there might be a 'guardian of time' type of character who tries to stop Caroline from changing the past, creating a conflict between her intentions and the natural order of time.
One common plot device is time travel itself. For example, the protagonist might accidentally travel back to the era when the Phantom first haunted the opera house. Another is the alteration of historical events. The character could change something in the past that has a big impact on the present in the Phantom of the Opera world. Also, the discovery of lost secrets from that time period often plays a role. Maybe the character finds a hidden diary of the Phantom that reveals his true motives and past, which then drives the rest of the fanfiction story.
One common plot twist could be that Naruko discovers she has the power to change not only her own fate but also the fate of the entire village. For example, she might prevent a major disaster that originally happened in the past. Another could be that she finds out a hidden truth about her family or a powerful jutsu that was lost in time. Maybe she realizes that a person she thought was an enemy in the present was actually a friend in the past and has to figure out how to reconcile that in the future.
Well, sometimes in these fanfictions, a plot twist might be that Sirius goes back in time and discovers a hidden truth about his family. Maybe he finds out that there was a secret alliance or a hidden enemy within the Black family that was influencing events all along. This could completely change his perception of his family's past and his place in it. Also, he could go back in time and end up being involved in a different kind of magic that was lost in his original time, like an ancient form of magic that has the power to either save or destroy the wizarding world.
Often, Dean will go back in time and accidentally change something small that has huge ripple effects on the future. Like he might save someone who was supposed to die, and then that person ends up causing a lot of chaos in the future that Dean has to fix. This creates a cycle of trying to set things right again. Another plot twist could be that when he goes back, he meets an alternate version of himself or his loved ones that are very different from what he knows, and he has to figure out how to deal with them.
A common plot device is the existence of a hidden magic that has been forgotten or suppressed. Harry stumbles upon this magic and realizes its potential to reverse death. There could also be a connection to the afterlife. For example, Harry might have to journey to the afterlife realm and bargain with the forces there to bring someone back. And sometimes, the dead themselves play a role in their own resurrection. They might communicate with Harry in dreams or visions, urging him to find a way to bring them back.
One common plot device is the knight - in - shining - armor trope. Annabeth could be a damsel in distress saved by a heroic knight, or she could be the one with the knightly skills herself. Another is the mystery of a forgotten castle or ancient relic. She might be on a quest to uncover its secrets. And of course, there's the political intrigue in the medieval courts. Maybe she has to navigate through power struggles between lords and ladies.
One common plot device is the accidental time travel. For example, a mage could be casting a spell and something goes wrong, sending them back in time. Another is the use of ancient artifacts. These artifacts might have the power to open portals to different time periods. Also, prophecies often play a role. A character might be sent back in time to fulfill a prophecy that will save Azeroth in the future. This can create a lot of interesting storylines as the character has to navigate a world that is both familiar and very different from their own time.