I've Been Killing Slimes For 300 Years And Maxed Out My Level is an isekai series where the protagonist Azusa, after dying from overworking, reincarnates as a powerful immortal witch determined to live the slow life. However, when she maxes out her level after 300 years of killing slimes, hilarity ensues as word about Azusa's power spreads across the land, sending many different people her way. The anime adaptation's first season recently wrapped up, and fans are already hoping it'll be renewed for a second season.
There is no doubt that the protagonist is very strong, but there are many other characters who are also a force to be reckoned with. From Shalsha's deadly magic to Beelzebub's brute force and transformations, fans adored watching this colorful cast of strong characters.
10 Eno Is A Weaker Version Of Halkara
Eno is great at disguising herself and crafting some potent potions, one of which turns out to be super popular. However, her wish to both be popular but also not too well-known makes it hard for her to have a successful business until Azusa encourages her to sell her wares publicly while wearing a disguise and portraying a character.
Eno hasn't seen any combat in the series yet, but it's likely that her expertise in potions and disguises won't help her much in the way of battle, even when compared to another inexperienced combatant like Halkara.
9 Halkara's Medical Expertise Makes Up For Her Combat Incompetence
Halkara's clumsiness and lack of combat experience don't help her much in battle, but her medical expertise is unmatched by most characters in the series, save for Azusa and Eno. Her antics cause a lot of accidents and misunderstandings throughout the series, as demonstrated when she was almost executed for accidentally headbutting the Demon King Pecora.
However, she's also the successful owner of several factories producing the fantasy-equivalent of energy drinks that are popular with everyone, demons like Beelzebub included. Her medical expertise also comes in handy when assisting her friends and cabinmates as well, even if she's the cause of a lot of their problems in the first place.
8 Falfa May Be A Slime Spirit But She Hasn't Shown Off Her Skills In Combat Yet
As a slime spirit, Falfa likely has powers similar to her powerful sister Shalsha. However, Falfa herself hasn't engaged in combat in the series yet, so it's unknown whether she has any magical abilities if at all. However, considering that Shalsha's whole being is made up of many fallen slimes, fans theorize that Falfa's a strong being in her own right; she just hasn't had a chance to show off her abilities yet.
7 Shalsha Almost Defeated Azusa, But She's Also A Glass Cannon Herself
Shalsha is introduced as being a fairly powerful slime spirit. Despite Shalsha nearly killing Azusa as vengeance for all the other slimes Azusa killed in the past three hundred years, Shalsha is surprisingly easy to defeat and can be considered a glass cannon. This is because Shalsha has no abilities to defend herself from anyone else attacking her. Laika easily defeats her with a tap on the head, immediately knocking her out.
Even worse, Shalsha cannot use that same spell again for at least another fifty years since it needs time to recharge. When this knowledge is revealed, Shalsha finally puts aside her need for vengeance and becomes a daughter to Azusa as Falfa did.
6 Flatorte Is A Powerful Dragon But Was Nowhere Close To Defeating Azusa
Flatorte comes from the Blue Dragon Tribe, an opposing faction to Laika's Red Dragon Tribe. After Flatorte and other blue dragons crash Laika's sister's wedding, Azusa and her friends are forced to defend themselves. There is no doubt that since Flatorte is a dragon, she probably has enough power to rival Laika.
However, Azusa easily beats Flatorte and forces her to pay not only for the damages done to the wedding, but also has her and the rest of her tribe sign a peace treaty with the red dragons to stop their constant feuding.
5 Laika Stood No Chance Against Azusa Despite Being A Dragon
Laika was introduced in the first episode of the anime after she destroys Azusa's house while challenging her to combat. Of course, despite being a powerful dragon and easily wrecking the house, she's no match for fighting Azusa herself.
Laika's shapeshifting abilities help her transport her friends to other places safely, and she also demonstrates her immense strength several times by defending her friends from harm and by reconstructing Azusa's house after she initially destroyed it. Even if Laika isn't the most powerful person in the series, she's definitely a strongly gifted friend anyone would want on their side.
4 Rosalie's Ghostly Self Makes Her A Hard Target To Reach
Rosalie was introduced after she started haunting the area of Halkara's newest factory, and it's revealed that as a ghost, she can possess people and make items levitate. Rosalie hasn't participated in any combat yet in the series, but her abilities would make it easy for her to quickly pick up any item and use it as a weapon when necessary.
Additionally, her intangibility as a ghost also makes it hard for opponents to get rid of her unless they know exorcism or other ghost-destroying strategies. Even then, it was hard to separate Rosalie from a then-possessed Halkara.
3 Pecora The Demon King Rightfully Earns Her Title With Her Battle Prowess
Pecora is the Demon King, and her powerful skills in combat against Azusa easily show off her prowess as a strong demon. Despite being pint-sized compared to Azusa, she easily swings around a giant greatsword with ease, on top of having several magical abilities.
Additionally, her ways of manipulating the people around her by using her cute looks and innocent-seeming demeanor are a boon both in and out of combat. This strategy could make many potential foes and allies alike underestimate her abilities, making it easy for Pecora to get the drop on opponents when she gets the opportunity.
2 Beelzebub Is The Only Person Who Stood A Chance Against Azusa In Combat
Beelzebub is one of the most powerful characters who have appeared in the series so far and the only character who proves to be a great opponent against Azusa other than Shalsha and Pecora. She can shapeshift into other forms such as a fly, which she used to spy on Halkara and the others at Azusa's cabin early in the series. Beelzebub can also fly during combat in her regular form, which she utilized against Azusa in both of their fights.
Beelzebub only lost the first fight because she accidentally flew into a previously set up magic shield Azusa made, instantly knocking her out. The second fight between her and Azusa, however,was much harder for Azusa to win, proving that Beelzebub is actually quite powerful in her own right.
1 Azusa Is Still The Most Powerful And Resourceful Of Them All And Has 300 Years Of Experience To Prove It
Considering that Azusa is the protagonist of the series, it's not a huge surprise that she's the most powerful person around. She's certainly powerful with her magic, as demonstrated in the first episode of the anime when she easily defeated Laika as well as several other characters later on, but she also has the resourcefulness to back it up and three hundred years of experience to work with. Even though she spent those past three hundred years defeating slimes, she also spent her time learning to brew potions, create new spells, and even defeat a couple of demons and dragons along the way.