Akuto Sai, the protagonist of Ichiban Ushiro no Dai Maō (aka Demon King Daimaō), is a very powerful character within the series’ setting, especially after he fully awakens his demonic king powers, but he’s not an “omnipotent” or multiversal-level entity in the broader anime/manga sense.

Basic Power Level in the Story

In the world of Ichiban Ushiro no Dai Maō , Akuto starts out as a fairly strong magic academy student, but his real strength rapidly skyrockets once he embraces his role as the Demon King. He’s far above average mages and skilled enough to easily defeat expert ninjas, elite academy students, and even high‑ranking magic users in combat.

  • He’s physically strong enough to lift and move a massive magical warship (the Genkaku) that’s about 350 meters long, which puts him in the “city block” or “large structure” lifting/strength tier in that setting.
  • He can fight multiple high‑level opponents at once and win, often with minimal effort, especially after he fully awakens.

Key Abilities & Skills

Akuto’s strength comes from a mix of high mana, physical power, a unique fighting style, and a wide range of versatile magic abilities.

Core magical powers:

  • Mana manipulation / absorption: He can absorb mana from others, steal their attacks, and reflect them back, making him very hard to hit with magic.
  • Explosion manipulation: He uses mana inside his body to create powerful explosions and enhance his physical attacks.
  • Forcefields & barriers: He can create strong mana barriers to protect himself and allies from attacks.
  • Healing & regeneration: He can heal serious injuries (like a severed arm) in seconds, showing monstrous vitality for a human‑level mage.
  • Electricity & air manipulation: He can summon lightning and control air, creating powerful wind and storm attacks.

Physical & combat skills:

  • Hua Jin martial art: He learns a high‑level martial art from the academy headmaster that lets him control every muscle in his body, allowing strength, speed, and precision far beyond normal humans and mages.
  • Enhanced senses & extrasensory perception: He can sense mana patterns to detect enemies and read their movements, making him very hard to sneak up on or surprise in battle.
  • Gun mastery & homing attacks: He’s extremely skilled with guns, even after little training, and can magically alter bullets’ paths to track and hit targets.

High‑tier abilities (post‑awakening):
Once Akuto fully embraces his Demon King powers, he gains:

  • Flight (via magic wings).
  • Paralysis & telekinesis (controlling others’ bodies with mana).
  • Telepathy / mind control (being able to influence or kill with a glance in some states).
  • Self‑sustenance: He eventually stops needing to eat, sleep, or breathe, making him extremely durable and hard to wear down.
  • Information analysis / “Life Logs”: He can access the complete history of every human (thoughts, actions, ideals), giving him near‑perfect knowledge in the story’s context.

How Strong Is He Compared to Other Characters?

Within Ichiban Ushiro no Dai Maō ’s world:

  • Akuto is easily among the strongest beings once he’s fully awakened, capable of taking on and defeating entire armies of elite mages and ninjas.
  • He’s strong enough to fight across dimensions and exist in higher realms, but his power is still framed as “peak Demon King” level, not universe‑busting or higher.

Outside his own verse, in common power‑scaling debates:

  • Akuto is usually placed in the high tier for a magic school/isekai-style series , roughly comparable to late‑series high‑level mages in series like Mahouka or To Aru (but not quite at the very top tier of those worlds).
  • He’s not considered multiversal or cosmically strong like some characters in Demonbane , Medaka Box , or Date A Live ’s higher tiers; he’s more in the “planet-level with some higher capabilities” range in fan discussions.

TL;DR – How Strong Is Akuto Sai?

  • In his story: Very strong — top tier mage, can lift 350m ships, fight armies, has insane regeneration, and accesses all human history.
  • Abilities: Absorption, explosion, barriers, flight, paralysis, telekinesis, healing, electricity/air magic, and a super martial art (Hua Jin).
  • Vs. other anime: Strong for a “magic academy” protagonist, but not on the same level as multiversal or reality‑warping gods from the biggest verse.

If you’re thinking “how would he do in a vs. battle vs. X?” his exact placement depends on how strictly you interpret the author’s highest statements, but in most power-scaling communities, he’s seen as a high-end fantasy-level hero, not a cosmic one.

Information gathered from public forums or data available on the internet and portrayed here.