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In Tensura: King of Monsters, you play as Rimuru Tempest, the reincarnated slime and leader of Jura Tempest Federation. Love him or hate him, Rimuru is a permanent face in your team. Is he really “not a bad slime” like he always claims to be? Read on to see how you can understand Rimuru better and make this “not bad slime” a lot better.
Rimuru’s skills
Initially, Rimuru starts with only 3 skills. Ultimately, the slime will be able to learn another 12 more by devouring Cores unlocked by playing the story. With up to 15 skills at his disposal, Rimuru is the only character in Tensura: King of Monsters with a customisable skill set. However, he can only equip one auto attack, one ultimate skill, one synergy skills and two different sets of aptitude skills.
Here is a look at all of Rimuru’s skills:
Ultimate Skill
| Name | Black Flame Slash | Black Lightning | Mystery Cooldown |
| Unlocked At | Available from start | Chapter 2-1: Lizardman Gabiru | Chapter 5-20: Animal Kingdom’s Purpose of Visit |
| Ability | 260% single target DMG | Costs 20 mana, CD for 0 round at the beginning, 2 round CD thereafter | 220% DMG to all enemies | Costs 40 mana, CD for 0 round at the beginning, 2 round CD thereafter. | Reduces one ally’s ultimate skill CD by 1 round Costs 20 mana, CD for 0 round at the beginning, 3 round CD thereafter |
| Comments | Compared to most characters’ ultimate skill, it is quite bad. Use it only if you really need the single target DMG. | Since there are not too many characters with ultimates that target all enemies, consider using this if you do not plan to use Mystery Cooldown or if you need to deal more damage. | Excellent. One of the best support-type ultimate skills in the game. When paired with Effective Use, it is possible to spam 2-round CD ultimate skills every single round. I.e. permastun with Christmas Shion/Shion [Kijin], immortality with Trya. |
Auto Attacks
| Name | Curvy Combo Slash |
Moonlight – Sword Shadow |
Healing Potion |
| Unlocked At | Available from start |
Chapter 2-12: Alliance formed! |
Chapter 5-10: Combat Drill (32) |
| Ability |
Deal 90% single target DMG twice |
Deal 107% DMG to a column of enemy units |
Restore HP to the ally with the lowest HP, equivalent to 100% of Rimuru’s ATK |
| Comments |
180% single target DMG is actually a decent figure. You’ll probably want to use this 90% of the time. |
Bad. You will need an entire column of 3 enemies for this to be worth it, and even then, Curvy Combo Slash is better most of the time. |
There might be some strategies where you need to heal an ally. However, you will usually save more HP by killing enemies quicker. |
Synergy
| Name | Vacuum Absorption | Storm Strike | Roundhouse Slash |
| Unlocked At | Available from start |
Chapter 2-6: 7-day Promise |
Chapter 3-20: Starved – Predator |
| Ability |
If the enemy is knocked back, deal 113% DMG to the target, causing it to fall to the ground |
If the enemy is suspending, deal 113% DMG to the target, knocking it back |
If the enemy is knocked back, deal 38% DMG to the target 3 times, causing it to suspend |
| Comments |
Use this depending on your team’s synergy. |
Use this depending on your team’s synergy. |
Use this depending on your team’s synergy. |
Aptitude
| Name | Inspiring Command | Mana Abundance | Effective Use |
| Unlocked At |
Chapter 3-10: Souei’s Promise |
Chapter 4-10: Combat Drill (25) |
Chapter 4-20: Priceless Monster |
| Ability |
The allied unit 1 square in front of Rimuru launches one extra auto attack every round |
Restore 20 mana after Rimuru uses a synergy skill |
At the end of the round, Rimuru consumes all remaining mana. For every 20 mana consumed, reduce Rimuru’s ultimate skill CD by 1 round. |
| Comments |
Excellent. Place your ally with the highest auto attack DMG in front of Rimuru and the ally will inflict even more pain. |
Perfect for teams that rely on synergy and ultimate skills. Avoid this if your team does not use synergy. |
You’ll only want to use this with Mystery Cooldown. Rimuru’s other ultimate skills are not great enough to warrant their use every single turn. |
Aptitude
| Name | Urgent Treatment | Concentration | Get Done |
| Unlocked At |
Chapter 6-10: Combat Drill (40) |
Chapter 6-20: Hold Back… |
Chapter 7-10: Combat Drill (48) |
| Ability |
From round 3 onwards, at the end of each round, restore 8% Max HP to the ally with the lowest HP |
Every round, Rimuru receives 30% less DMG until he launches an auto attack |
At the beginning of battle, increase all allies’ ATK by 5% for 3 rounds |
| Comments |
Might be useful in some strategies, but 99% of the time, Get Done is better. |
Useful in situations where you want Rimuru to act as a tank, like soaking up DMG from dangerous single target ultimates. Also works in certain compositions when facing against Orc Disaster in Subjugation. |
Your go-to aptitude 90% of the time. While 5% ATK increase for 3 rounds is low compared to Benimaru [Kijin]’s aptitude (20% ATK increase), more ATK is always better. |
The Good, the bad, and the slimy
In Tensura: King of Monsters, Rimuru shines as a support character. Mystery Cooldown paired with Effective Use is the only way to make allies’ cooldowns nonexistent outside of Space Gap. Use both of these skills if you are relying on your allies’ ultimate skill. For a team that relies on auto attack, like Gabiru and Hakuro [Kijin], use Inspiring Command and Get Done.
Even though characters like Shion [Ogre] can tank better than Rimuru, the slime can also serve as a tank due to his naturally high HP and DEF. However, since you will be placing him in front most of the time to tank, Inspiring Command does not pair well with this strategy. Consider using him as a tank if you are using the Mystery Cooldown + Effective Use combo.
Offensively, Rimuru’s kit is bad. He simply does not have any aptitudes that boost his DMG output for him to be an effective damage dealer. You can still count on him to squeeze out a little bit of extra DMG, but he will never be your main DMG dealer. Making things worse is the fact that he cannot equip gear, and by extension, cannot gain set effect bonuses.
While Rimuru can also be a healer, you will rarely need one in your team. Even then, units like Treyni are much better at the job.
Memory Crystals and special buffs
In addition, Rimuru has even more passive unlockable abilities that are separate from his Aptitudes. These passives buff not just Rimuru, but also the entire party. Unlike his normal skills, these buffs are always active and cannot be equipped or unequipped.
To unlock these party-wide buffs, players will first need to complete Story chapter 4-1 to unlock Rimuru Event. The goal of this mode is for players to fill in all the puzzle pieces by beating enemies. Once all puzzle pieces are filled, the Memory Crystal of the respective puzzles can be devoured to gain new buffs.
Note that every time you collect a new puzzle piece, the strength of the enemies in the remaining puzzle pieces increase. It does not matter if you start by getting the top-left puzzle piece or somewhere in the middle.
The roman numeral attached to each puzzle contains the corresponding Memory Crystal. Puzzle I unlocks Memory Crystal I, likewise for puzzle V and Memory Crystal V.
Here is a list of each Memory Crystal and the buffs they provide:
Memory Crystal I: 5% ATK buff for all allies
Memory Crystal II: 5% DEF buff for all allies
Memory Crystal III: 5% max HP buff for all allies
Memory Crystal IV: 5% Crit buff for all allies
Memory Crystal V: 5% DMG reduction buff for all allies
While they might be small, any boost to your team’s stats is never a bad thing.
Tips and Tricks
Do not be afraid of sacrificing Rimuru! While it’s counterintuitive to let the main character get killed quicker, Rimuru does not have the same impact in fights as your damage dealers. If putting him behind your damage dealer to activate Inspiring Command still results in defeat, try placing him in front of the damage dealer to tank damage instead.
In Space Gap, Black Lightning coupled with the Soul Drawing Core relic can wipe out an entire enemy team provided there is at least a single enemy with HP low enough to die from the attack. This is a bug that works with any multi-target Ultimate Skill.
Buy Memory Shards in the market whenever you can! You are essentially spending Silver Coins to permanently buff Rimuru—an excellent trade-off.
As That Time I Got Reincarnated as a Slime continues airing (Tensura Nikki premieres in Spring), it is a given that the game will receive new content. Hopefully, Tensura: King of Monsters will add even more new mechanics to Rimuru soon, considering the absurd abilities which he gains in the future.
Check out our other Tensura: King of Monsters guides:
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I'm not an evil Slime! Would you like to hide in my stomach?
That Time I Got Reincarnated as a Slime: King of Monsters is a mobile strategy multiplayer online RPG game, an official game adaptation of the anime under the original writer Fuse's supervision! The game employs the state-of-the art 3D cel-shading technology to present to gamers the Jura Tempest Federation from the anime. In the game, players may summon monsters, collect characters from the original anime and build up powerful monster combat lineup. The game features a unique Devour system that allows players to develop their own Rimuru!
