What are Transmigration Stories?

TL;DR - Transmigration stories are the Chinese peer of Japanese Isekai (異世界).

Been scrolling your favorite tag on NU and don't know what to expect from transmigration stories?

Keep hearing someone refer to the system, agents, hosts, or transmigration?

No worries, I've got you covered :).

One way or another the protagonist finds themselves transported to another world. This can be due to the character dying in there previous world, but unlike Isekai death isn't a general requirement (insert truck-kun meme here). It's equally common for the protagonist to have transmigrated as a part of an assignment or punishment and be expecting to return to their own world at some point.

Once the transmigration has taken place, the protagonist finds themselves in another world. This world can be anything, but it's typically alt-historical, fantasy, alt-modern, or the world from a book/game/movie. They also typically retain their knowledge and memory from their previous life, while most or all of the other people in the world are natives who are unaware of transmigration.

In order to prevent the transmigration being immediately obvious, the protagonist is typically transmigrated into the existing body and life of one of the characters in the world. I've always thought that this was probably some type of murder but somehow that's basically never brought up and doesn't seem to matter to anyone... shrug.

Regardless, authors typically use Transmigration to provide relatable characters in unrelatable worlds, subvert expectations of archetypical stories, and allow readers to indulge in wild Chuunibyou (中二病) delusions as overpowered protagonists smash their way through whatever problems they encounter.

Some transmigration stories just proceed from this point so feel free to stop here and get back to reading, but a lot of them leverage a few more common patterns that are worth mentioning

Oftentimes authors feel the need to give some explanation for why and how transmigration happens and how a multiverse of different worlds exist to transmigrate between, and the typical answer is called The System.

The System is the power behind the scenes. It can be left vague or be well-explained and baked into the plot and world-building of the story. Either way, the system acts like the Dungeon Master of the transmigration universe, setting the rules for moving between worlds, and influencing the lives of characters within each world. For example, the system may consider that a certain world is out of balance and that the transmigrated character is responsible for bringing the world back into some desired state. In this example, it would also be super common for the character to decide that they don't agree with this mission, fall in love with someone in this world, and spend the rest of the story battling to avoid completing the mission set by the system. Fun times!

The character who is transmigrated into a new world is called the host. They often have knowledge of the system and even may have knowledge of what will happen in the future of the world that they're transmigrated to. This is where the Chuunibyou sets in because they start out with a bunch of unfair advantages. Given that they're often fighting the system I guess this is manageable, but it really gives a PC/NPC feeling to a lot of the encounters between the transmigrated character and other in-world opponents.

In order for the host to interact with the system and the world they may have access to one or more system agents. These system agents are programs/entities that represent the system and have direct interactions with the hosts. They can be guides, helpers, enforcement systems, or even just comic relief characters. I tend to think of them as the video game component of the story because typically the agents are only known to the host and follow some sort of rules or structure that allows them to be exploited or worked around.

Uh oh, I think I just realized that all transmigration stories are Matrix fan fictions... Maybe that should have been my TL;DR. Anyways, now that you know what transmigration stories are go forth and read with confidence!