Slime Taoshite 300-nen, Shiranai Uchi ni Level Max ni Nattemashita

In role-playing games, slimes are usually the easiest monster to kill, and because of that, they yield few experience points. But what would happen if you live long enough to keep defeating them for 300 years?

After many years of being a corporate slave, Azusa Aizawa abruptly passes away due to severe exhaustion. Seemingly headed for the afterlife, she meets a goddess who bestows her with immortality alongside a peaceful life in another world. There, Azusa enjoys her days tending to her farm, protecting the nearby village, and killing about 25 slimes per day—a routine that continues for at least three centuries.

However, this rather monotonous cycle begins to change when Azusa suddenly finds out that she has reached level 99—the maximum possible level—from slimes alone. Despite desperately trying to hide this fact in fear of ending her slow life, rumors of her strength spread nevertheless. Soon enough, various people throughout the continent, like the dragon Laika and the elf Halkara, start to appear at her doorstep—some seeking a battle, others asking for her assistance. Meeting friends and acquaintances who soon become family, Azusa finds she can live a life far better with others than when she was alone.

[Written by MAL Rewrite]

Azusa Main

Yuuki, Aoi Japanese

Laika Main

Hondo, Kaede Japanese

Falfa Main

Senbongi, Sayaka Japanese

Halkara Main

Harada, Sayaka Japanese

Shalsha Main

Tanaka, Minami Japanese

Beelzebub Supporting

Numakura, Manami Japanese

Flatorte Supporting

Waki, Azumi Japanese

Pecora Supporting

Tamura, Yukari Japanese

Rosalie Supporting

Sugiyama, Riho Japanese

Vania Supporting

Ozawa, Ari Japanese

Oowada, Tomoyuki Producer

Komatsu, Shouta Producer

Hasegawa, Yoshinori Producer

Nanbara, Mitsuhiro Producer

Reviews

Mar 23, 2025

-sigil-

Recommended

Slime 300 is a bit misleading because it does the bare minimum to consider itself an isekai. This can be seen by the start of the story, which only asserts itself as such to set itself up before moving on and quickly forgetting about it. The setup involves an ephebophiliac deity who takes pity on a woman named Azusa who dedicated her life solely to her job. She dedicated so much time to her job in fact that she just collapsed then and there due to the amount of both physical and mental stress she underwent. She took the literal saying of “don’t work yourself ... to death” and collapsed with it. Afterwards, the deity asks the now incorporeal soul if she has any wishes, to which she expresses her desire to be both youthful and immortal. And so, her wish is granted, and past life as an office worker, which has been cut short, can be reshaped to form an idealized life free from stress… or so she thought.

In her newfound slow life (in her words), she is spawned into a world that allows her to live the life she pleases. Now reincarnated as a witch, she moves into a large unoccupied house with many rooms. Given that she isn’t quite adjusted to her new slow life yet, she passes the time by making it a routine to kill slimes. Upon killing a slime, a handful of blue crystals would drop, which leads her to inquire about the currency in the city’s adventurer’s guild. To be a bit misleading again and to play around with the semantics, it’s not as much of a killing slimes anime because it’s more akin to a found family CGDCT. Semantically, “I have” would suggest that the slimes have already been killed. However, the story has to be set up in order for the killing to happen, so it strays away from the brief mention, even for a brief moment. The thing is, the story addresses this matter in a really uninspiring manner because it just skips over everything. Obviously, not all 300 years can be shown, but a little bit of scenery or a small compilation of time skips could’ve helped. The story is set up in a way similar to that one kid in school that would claim they did 100 push-ups but only claimed to do so because they started at 97. Regardless, Azusa gets caught up on killing slimes and unknowingly maxes out her level, hence the title.

After the time skip, she possesses both a great amount of powers (or perks) and respect from anyone around her, much like any other generic isekai protagonist. Being a witch, most of these perks pertain to witchcraft, with the most notable of these (besides immortality) being elemental powers resembling witchcraft. She was so caught up in her work that she neglected checking her progress with the adventurers guild for 300 years. It’s unclear why she was unable to check for level for over 300 years, but it at least adds to the overall absurdity of the plot itself. The world seems like a time capsule because it's remained practically unchanged for all 300 years. The only notable event that occurred throughout the three centuries was a plague, which is historically appropriate for a medieval-esque European village. Given Azusa’s reputation in the village, her quest for a slow and easy life slowly diminishes. As the series progresses, more and more otherworldly beings “take an interest” in her and join her family. Parenthood is appealing to a lot of people, but its practically the antithesis to a slow and easy life. Basically, she got set up.

Azusa as a character mostly ties into the story’s theme of “don’t work too hard and take it easy.” She’s also a humble person that doesn't like to brag, even though she can be a bit assertive here and there. Most of her character focuses on finding a balance between work and leisure. Given the tragedy in her previous life, she encourages others to not work too hard as well. This can be seen by her very hospitable nature, which makes her question the possibility of starting a “found family” under the pretense of acquiring both companionship and an easier life.

***Episode 1 spoilers***

The first character she meets, Laika, helps to demonstrate this. Much like those before her, she attempts to challenge Azusa in an attempt to make a statement that she is the strongest in the highlands after catching word of a spilled secret. The only difference between her attempt at it and other measly humans is the most notable, she’s a red dragon. Azusa attempts to dismiss this challenge under the pretense that it was simply a rumor and that she is simply seeking a slow life. However, Laika’s juvenile and prideful attitude makes her insistent in the face of hesitancy, which makes the unwilling Azusa give in. As the battle commences, Laika is shown to naturally possess the ability to breathe fire in her dragon form. Additionally, her size would prove that a good deal of agility would be needed in order to defeat her. Considering the witch’s newfound powers and humble attitude, she handles this in a timely manner. After playing defense for a bit, combining the elements would prove to be successful. Afterwards, a bit of dizziness causes her to collapse on Azusa’s house, which rightfully pisses her off. Laika, scared by her confrontational tone, pledges to repay her by helping rebuild her home. To her surprise, she shows up the following day in human form. The endeavor of reconstructing her house is a time consuming process, and without Azusa’s instructions to prevent Laika from exhausting herself, it wouldn’t have been done. Upon completion, she transforms into a dutiful maid to help Azusa ease into her new slow life. The message of not overworking oneself to death is transmitted from disciple to pupil.

***End of spoilers***

There are six other characters that join the family, but they’re either cute or forgettable. As of now, a well needed second season is in the works to hopefully flesh out the characters, since a good chunk of them join Azusa’s family halfway into the series. Despite the basic description provided earlier, I do have a favorite out of the seven, and that favorite would be Flatorte. Much like Laika, she too is a dragon. The most notable differentiator distinction that is found between the two would be Flatorte’s blue color and tail that pops up in her human form. In relation to the color blue, she also has weird hair loops that are reminiscent of Satania’s from Gabriel Dropout. Nevertheless, it is her personality that makes her stands out from the rest of the girls, mostly because she’s the most brash of the bunch. Much like Laika, she joins the family after losing a battle towards Azusa, the only difference is that a moral code was broken. Rather than be dishonorable, she pledges her oath towards Azusa under the ruse of fulfilling any of her orders. Given that Azusa is more adjusted to her new life as the series progresses, she finds a loophole and instructs Flatorte to live in any way she pleases. She mostly exists to compete for Azusa’s attention with Laika.

The audiovisuals are good because it aligns with the series’ intentions to be a cute moe thingy. Since its purpose is to be cute, the character designs must be well designed. Well, the series excels in this regard, since the character designs are Slime 300’s most commendable aspect. Excluding the slime twins who have similar character designs for obvious reasons, the rest have a distinct style that sets them apart from each other. Were it not for Azusa’s design, I probably wouldn't have picked up the series to begin with. In a few instances, her design would be swapped out with something more formal, with the only downside being the loss of a hat. Additionally, the backgrounds use a lot of soft colors that help the characters pop out. The only downside to the art itself is the dip in quality when it uses a bunch of different camera angles, because it makes the outlines vary in thickness. The animation also has a few dips in quality depending on the scenery, but it’s not as notable as its overall decency.

In conclusion, Slime 300 is a series that succeeds due to its simple premise and character designs. As the genre suggests, it’s an isekai by its name, but the premise of it is almost alluded to which can be seen by the brief mention of it at the beginning. Afterwards, it’s not mentioned at all and only serves as a motivator for change for the main character and her seeming subordinates. The message of a slow life is simple as its told, but after the first episode, it’s reinforced visually instead of audibly. The characters tie into the themes; Azusa even more so, which is why her character could be considered thematic. Not to suggest that her character role is limited to conveying these themes, because while it is important, the series does a good job of making her character seem human, which can be seen by a great deal of both her egotism towards herself and compassion for the people she cares for. The artwork, which uses soft colors stands out because the series understands it’s the main appeal. Overall, Slime 300 is a bit juvenile since it’s the basic moe slice-of-life shtick, but it works wonderfully based on what the series is trying to achieve.

If Azusa didn’t have a witch hat, the series would be a 6/10.

Reviewer’s Rating: 7

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Nov 11, 2023

Canner

Mixed Feelings

Slimes for 300 years is the DEFINITION of an average anime.

I watched this maybe a year or so ago, and I hardly remember a single thing about it. That should be all you need to know. It's not memorable. There's no substance. A good anime will have memorable plot points, characters, etc. This anime has nothing. It's a filler while you wait for other shows to come out.

It does shake up the Isekai trope somewhat, wherein the whole "transported to another world and figuring out what the hell is going on" arc is nearly entirely absent. The character has been in the alternate ... world for 300 years (shocker), and is blatantly overpowered with weak allies. Go figure. They try to draw away from their lack of substance with fan service and it does not work on anyone out of their prepubescent age.

However, it's not BORING, it is somewhat entertaining to have on in the background (dubbed) while you're doing something else.

This is a skip. If you're looking for something to get attached to.

Reviewer’s Rating: 6

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Nov 7, 2022

BlackBusterMAL

Not Recommended

English.
Well the title of this literal series tells us the plot of the anime, this is a temporary anime that you can watch on a Sunday to relax, the format is very similar to what sitcoms are since each chapter has a different plot and there is no apparent plot line to follow. I believe that this type of anime is created to pass the time and have fun from time to time, it does not contribute anything and the truth is that the situations it shows are not that funny, nor that entertaining, they are fine.
The characters are charismatic and each one has a ... different personality that makes them instantly recognizable, the main story goes nowhere and what you see are some days in the life of this group of girls.
The conclusion is that this anime is mediocre and although it sounds bad, the truth is that it is not bad to be mediocre, the episodes are fun and there are some better than others.

Español.
Bueno el título de esta serie literal nos dice la trama del anime, este es un anime pasajero que puedes verlo un domingo para relajarte, el formato es muy parecido a lo que son las sitcoms ya que cada capítulo tiene una trama diferente y no hay un hilo argumental aparente que seguir. Yo creo que este tipo de animes son creados para pasar el tiempo y divertirte de vez en cuando, no aporta nada y la verdad las situaciones que muestra no son ni tan divertidas, ni tan entretenidas, están bien.
Los personajes son carismáticos y cada uno tiene una personalidad distinta que hace que los identifiques al instante, la historia principal no llega a ningún lado y lo que vez son algunos días en la vida de este grupo de chicas.
Es conclusión este anime es mediocre y aunque suene mal, la verdad no está mal ser mediocre, los episodios son divertidos y hay algunos mejores que otros.

Reviewer’s Rating: 2

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