No, Diablo is Not the Strongest Demon in Slime

As one of the most powerful archdemons summoned from another reality, Diablo boasts prowess exceeding nearly any typical entity in the Slime multiverse. However, among the highest ranks of Slime‘s fighters, Diablo does not stand at the utter pinnacle – with a handful of uniquely mighty characters surpassing even his formidable strength.

Section 1 – Origins and Abilities of a Formidable Archdemon

Hailing originally from the world of Isekai Maou as one of the primordial demons, Diablo‘s origins trace to the entity "Noir" – considered the apex demon next to his sole rival, Guy Crimson. As Noir, Diablo was strong enough to warp and destabilize surrounding reality itself through his demonic aura.

After being summoned to the Slime universe, Diablo retains his mastery over reality-bending magic and skills honed across 20,000+ years battling as one of the strongest demons in existence. Some of his capabilities include:

• Reality-warping black magic
• Darkness and fire elemental magic up to level 150
• True teleportation behind opponents
• Nullification barriers against magic
• Telekinesis and gravity manipulation
• Expert swordsmanship skills

As the chart shows, Diablo‘s comprehensive combat capabilities excel in nearly every category – rendering him stronger than even most Demon Lords.

However, Slime contains a handful of uniquely fearsome entities exceeding even the formidable primogenitor demon…

Section 2 – Slime Characters Surpassing Diablo‘s Strength

While still mighty in the Slime universe, at least 5 notable characters firmly overpower Diablo in their most powerful forms:

True Dragon Rimuru

After evolving into a True Dragon, Rimuru gains the strength to destroy tens of thousands of universes. His skills also scale with and amp the abilities of his subordinates, boosting Diablo‘s powers as well but still remaining utterly dominant himself.

Milim at Full Power

A direct daughter of primordial dragon Veldanava, Milim boasts enough raw energy in her peak form to wipe out entire star systems instantly. She also scales higher than Diablo due to being on the same plane as True Dragons.

Guy Crimson and Rudra

As Diablo‘s only worthy rival in Isekai Maou, Guy Crimson retains utter dominion over life, death, and souls – granting powers even Rimuru Tempest cannot match without absorbing Veldanava‘s memories.

Reinhard and Feldway

Possessing broken skills that transcend normal power scaling logic, both Reinhard and Feldway have means to defeat opponents massively stronger than themselves like Ultima and Masayuki. As such, they likely can overwhelm even Diablo through similar reality-warping abilities.

Here is a chart ranking estimates of the top 10 strongest characters in Slime‘s cosmology:

As demonstrated in the table above, at full power the likes of Guy Crimson, Rimuru, and Milim decidedly eclipse even the mighty Diablo and most other Demon Lords in combat talent.

Section 3 – Standing Among Tempest‘s Forces

Yet despite champions with even greater strengths arising in Slime‘s cosmology, Diablo still stands out as one of the singularly most mighty entities affiliated with Rimuru Tempest‘s nation.

As Tempest‘s strategist and secondary leader to Rimuru, Diablo‘s comprehensive abilities likely firmly place him as 3rd strongest being within Tempest itself – though granting Velodora the edge is highly debatable.

Matched against fellow Tempest patrons and demon lords, none besides Velodora could defeat Diablo in a 1v1 battle:

Furthermore, against warriors like Hinata Sakaguchi possessing world-class speed and attack abilities but lacking experience – Diablo‘s proficiency prevails against raw power. His skill and precision outmatch Hinata.

So while eclipsed by Patrons and Primordials, Diablo remains Tempest‘s most consummate fighter – though still serving loyally under Rimuru‘s leadership.

Section 4 – Closing Thoughts

In closing, Diablo stands undeniably as one of the mightiest demons across the known Slime cosmology. Yet several unique beings ultimately claim utter dominance and more comprehensive fighting capabilities than even formidable primogenitors like Diablo.

Nevertheless, his profound years of experience coupled with reality-warping magic still enable the archdemon to contend with nearly any opponent. Raw strength alone does not determine victory or superiority. So while no longer the singular #1 demon, Diablo remains an icon of power within the Tempest nation and Rimuru‘s circle of allies.