I want a manga in where the MC is a genius, not in academics but in real life and in times of conflict such as in Code Geass and Chouka kou. I don't want one of those perfect MCs from shoujo and Josei mangas and I prefer it be shounen or seinen. It doesn't have to be mental capabilities, it could just be the MC being extremely good at whatever he does or learns quickly as in the main from Team Medical Dragon I don't mind Sports if its like the main from One outs. I prefer a lot of action but not battle mangas, and it would be even better if it was supernatural. The MC could be a strength type Genius such as Viole from Tower of God or the cunning type such as Koon from the same manhwa. But I don't want manga like Bartender and Dr. Frost

Read:
KUROKO NO BASKET
Team Medical Dragon
Dr. Duo
Black Haze
Gamble Fish
Liar Game
Itsuwaribito Utsuho
Ansatsu Kyoushitsu
Dr. Frost

[img]http://i.imgur.com/Z7HIWCD.jpg[/img]

For believably clever main characters check out FUKUMOTO Nobuyuki.
Particularly Akagi and Kaiji.

Aoki Hagane no Arpeggio (does naval battles count as a "battle manga"?)
Baby Steps
Black Lagoon (maybe)
Densetsu no Yuusha no Densetsu
Gunka no Baltzar
Historie
Lessa (maybe)
Mahouka Koukou no Rettousei*
Maoyuu Maou Yuusha - "Kono Watashi no Mono Tonare, Yuusha yo" "Kotowaru!"
Master Keaton
Naqua-den*
Onepunch-Man*
Peak (IM Gang-hyeok)
Rain
Spiral - Suiri no Kizuna
Yuusen Shoujo - Plug-in Girl*
Zetsuen no Tempest

Asterisks (*) denote the manga that I think might be battle manga, though I'm not really sure what criteria you're judging that...?

My list.

Jin
Feng Shen Ji
Historie
Vinland Saga
Master Keaton
Monster
Teppuu
The Gamer
Until Death Do Us Part

There you go. I filtered out the bad and mediocre one. While some of the earlier recommendation actually fit the one you asked for, like Onepunch-Man, Mahouka Koukou no Rettousei and Rain, but IMO, the character is so OP, that it actually break the WORLD BALANCE.

You know, that one element for it to be a good, organic world. Both manga kinda feels like the world was actually created for the sole purpose of telling (not showing) MC badassery. And that's a bad storytelling.

And the rest is... well... pulling off a good Badass Protagonist troupe is kinda hard, and the rest kinda fall short. In the exception of Black Haze, a surprisingly decent with pacing problem, the enjoyable Onepunch-Man also with pacing problem in addition of unbalanced world, safe to say, that criteria you're looking for, the good one, is pretty rare.

So, in that note, good look with your search 🙂

Quote from Suxinn

Aoki Hagane no Arpeggio (does naval battles count as a "battle manga"?)
Baby Steps
Black Lagoon (maybe)
Densetsu no Yuusha no Densetsu
Gunka no Baltzar
Historie
Lessa (maybe)
Mahouka Koukou no Rettousei*
[m]Maoyuu Maou Yuusha - "Kono Watashi no Mono Tonare, Yuusha yo" "Kotowaru!& ...

When I say battle manga, I mean it when one battle takes like 30 chapters to end and Thanks for all the suggestions 🙂

[img]http://i.imgur.com/Z7HIWCD.jpg[/img]

Ares
Gamaran
Kidou Senshi Gundam Seed
Canonically, Ichigo Kurosaki is considered a genius when it comes to combat in Bleach but we never really see the process of that, just the results.

I'm a jack of all trades but master of none. Too many jars and not enough hands.

The king’s avatar (Quan zhi Gao shou) might fit the bill.