That Time I Got Reincarnated as a Slime

Everything About Fiction You Never Wanted to Know.
One slime (and his army) going against the world.

Satoru Mikami was a 37-year-old office worker with no girlfriend who lived in Tokyo. His colleague, Tamura, asks him for marriage advice. Satoru meets him with his partner, Miho, but a passing robber stabs Mikami. After having some final thoughts, he dies and reincarnates into another world as a slime. He learns about how he has the ability, Predator, where he can consume other monsters to obtain their abilities. The former human begins to explore the cave he was in and comes across an imprisoned dragon, Veldora. He then makes friends with Veldora and a new name, Rimuru Tempest. Rimuru then consumes the prison and Veldora to break his entrapment. This event is only the start of his journey as he meets different races and influences the world without knowing it.

That Time I Got Reincarnated as A Slime or Tensei Shitara Suraimu Datta Ken started as a web novel on Shosetsuka ni Naro in 2013 and ended in 2016. The light novel is illustrated by Mitz Vah and published by Micro Magazine in 2014. The manga is illustrated by Taiki Kawakami and started in 2015. The anime's first season was produced by 8bit and premiered on October 2, 2018, and ended on March 26, 2019. A second season aired on January 12,2021, instead of 2020 because of the Covid-19 pandemic.
Tropes used in That Time I Got Reincarnated as a Slime include:
  • Alternate Realm Boon: The middle-aged protagonist, Satoru Minami, gets killed by defending his subordinate from being stabbed. He reincarnates into another world as a slime. Due to how he died a virgin, he gained the Unique Skills of Great Sage along with Predator, and other skills.
    • Said world receives so many people from other worlds that they have an in-universe term to designate them, "Otherworlders". Otherworlders tend to have at least one Unique Skill based on their mental state, and those with weaker minds would gain none. There are three types which are Strays, Reincarnated, and Summoned:
      • Strays are Otherworlders that come to the world by coincidence.
      • Reincarnated are people who have died and reborn into the other world as natural inhabitants, much like Satoru.
      • Summoned are those who are transported to the world by a magic ritual.
  • Anatomy of the Soul: Humans and Monsters both have souls and require a body due to their fragility. Reincarnators can survive with just their soul through certain Skills that can strengthen them. There are three parts of the soul:
    • Nucleic Heart is the core where Skills are engraved and cannot be removed unless certain conditions are met.
    • Ego is the 'being' where individuals get their sense of self and contain their memories. It's a film of energy around the Nucleic Heart. The loss of the Ego can result in insanity and losing access to skills.
    • The Astral Body is the soul's container and comes in the shape of the physical body. It is a medium where that can preserve the soul for reincarnation. It can also be used as a body for spiritual beings if they have the power to solidify it.
  • Background Magic Field: Magicules are a special kind of energy that can affect physical matter and phenomena. A lifeform can use magic, Skills, Arts, and weapons that can affect incorporeal matter to do damage. They would be comparable to Mana or MP like what's found in games. Magicules are governed by different rules and don't follow physics, such as the laws of Thermodynamics or Energy Conservation.
  • Elemental Embodiment: Elementals embody a specific element created from natural energy. They can take in magical energy related to their respective element. Unlike normal magic, their elemental powers obey the laws of physics. Chosen Heroes can make a symbiotic relationship with Elementals of either Light or Darkness. Fairies are also Elementals, but they incarnate into a physical body.
  • Elemental Rock-Paper-Scissors: The eight elements of space, earth, space, wind, water, fire, light, and darkness. The relationship for six of the eight works like this: earth > space > wind > water > fire > earth. Light and darkness counter each other equally. The element of time is also the strongest and most effective against the other eight elements.
  • Evolutionary Levels: Races besides Humans, Elves, and Dwarves are capable of evolving where they can achieve higher forms. Goblins can evolve into Hogoblins for males and Goblinas for females. Direwolves can evolve into Tempest Wolves or a parallel line of Black Direwolves.
  • Evolution Power-Up: Certain races can evolve into a more powerful form. One method is by being named by a higher being and given a name.
  • Functional Magic: Magic embodies ideas using Magicules for specific effects. They create physical phenomena, but their results can be spiritual, too. There are four main types of magic:
    • Elemental Magic or Aspectual Magic uses Magicules directly to ben the laws of nature based on the caster's mental power and incantations. More potent spells need greater focus and longer chants.
    • Spiritual Magic is similar to Elemental Magic and has a plethora of offensive spells. This form uses the power of spirits (usually Elementals) by using their energy as a catalyst to execute their power. The spells are based on natural phenomena and obey the laws of physics, which means they can be used even in an anti-magic field. It doesn't need chants and just needs a connection with a contracted spirit. Higher-level users can summon their spirits and use their power by having them attack or fuse with their summoner.
    • Holy Magic uses faith to manipulate divine energy and purifies Magicules that can even make Miracles. It's considered a form of spiritual magic due to its requirement to make a pact with a divine spirit. This form of magic is used for healing but lacks offensive spells, yet they are effective against almost any monster. Advanced users with enough faith can use Divine Miracles, which uses Spiritons, the basic building block of magical energy, for power effects.
    • Summoning Magic where a living being can summon another from a different plan of reality but needs to master spatial magic to accomplish such a feat. It's usually used to summon Monster, Elementals, and Demons.
    • Other types of magic don't fall into the four types: Engraving, Physics, and Necromancy. Engraving Magic is where users enchant people or objects with a spell to use magic without skill or knowledge. Physics Magic is any magic that has a physical effect but doesn't use Magicules and can't be interfered with by them, which is useful against anti-magic. Necromancy is a type of spiritual magic that involves using negative emotions of the dead and evil spirits.
  • The Hero: Heroes are usually the counter to Demon Lords blessed by an Elemental of Light or Darkness. As a class, a Hero can make a symbiotic relationship with an Elemental that forms a Hero's Egg. When this egg hatches, they will become an Awakened Hero. A person can be given the Title of Hero by the masses, making their destiny cross with the Demon Lord.
  • Our Demons Are Different: Daemons or Demons are Monsters that do not usually have a physical body. These monsters exist in the Spiritual World, where they would wander without any thought. The older a Daemon is, the stronger they are. They often would train their magic and skills instead of trying to gain strength.
  • Our Goblins Are Different: Goblins are monsters who are short and are one of the weakest monsters. Their strength comes from numbers, but they lack individual advantages. They can, however, evolve into a Hobgoblin, where they become more human-like except with green skin and fangs. They suffer from lower fertility while gaining a boost in strength and lifespan.
  • Our Ogres Are Different: Ogres are a high-class race but are low in numbers. They are two-meter tall humanoids with horns and red, pink, grey, or tan skin tones. Their culture resembles that of feudal Japan. Despite looking brutish, they are rather sophisticated but carry a significant physical strength.
  • Our Orcs Are Different: Orcs are a race that looks like anthropomorphic boars. Orcs have a high reproductive rate along with strength on par with Hobgoblins and Orges.
  • Our Spirits Are Different: There are Spiritual Lifeforms that originate from the Spiritual World. They do not have a physical body, but they can have vessels. Beings that fall under this category are Elementals, Demons, and Angels. There is an intriguing power structure that the three share: Angels have an advantage over Elementals, Elementals have an advantage over Demons, and Demons have the advantage over Angels.
  • Power Levels: Rank is a system made by the Free Guild to evaluate the strength and danger of Adventurers, Monsters, and other entities. Adventurers and Monsters are ranked from F to A, where upper echelon have a '+' while the lower have '-'s. There are Threat Levels for rank A and higher: A, Special A, S, and Special S.
  • RPG Mechanics Verse: The World System monitors the Magicules' flow and the distribution of skills. It also administrates the circulation of souls. The Voice of the World is an entity connected to it that acts as a program. It communicates with people about skill acquisitions, monster evolutions, and world changes.
  • Shout-Out:
    • In Episode 6, Rimuru uses the phrase, 'I'm not a bad slime!' which is a line from the friendly slimes in the Dragon Quest series.