just wondering if anyone can point out some manga or manhwa with a normal guy, in a world with superpowers, who also sometime has a power
eg Mx0, Iris Zero, Index, Railgun

Crepuscule (Muchi) he is the only human in a world of vampires(after like 3 chapters)

It's a webcomic, but Tower of God fits that description perfectly.

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Go to work, send your kids to school;
Follow fashion, act normal;
Walk on the pavement, watch T.V.;
Save for retirement, obey the law.
Repeat after me: I am free.

I don't know if you can count them in but:
Zero no Tsukaima most people in that world can use magic.
Maburaho most people can use magic for a very high number of times, but he can only use it three times (anime>manga).
Rosario to Vampire normal guy in a school of "monsters" (vampires, werewolves, etc.).

Also your description fits very well Fate/Stay Night game and anime (I never read the manga so I can't speak for that one but I suppose it's ok).

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What I like in Trivial Pursuit style. Pick your category:

Index,Railgun
WHAT is he a nomal guy
in what way is he normal
he have the best power of them all
and if thats not all
he gains more later on

princess resurrection hiro is normal he usually is boring, normal and weak and his powers only awaken when hime is in danger


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currently reading: Nyotai-ka
please support me

I don't think it really counts because even though he can't use magic....

Cromartie High School is about a normal guy in a school of crazy delinquents, who sometimes becomes the craziest of them all.

Back on topic, I think Suzumiya Haruhi no Yuutsu fits, because the protagonist is the only normal person in a group of friends who all have powers. I don't think he gets any powers at all, but I do remember him doing some time traveling (at least in the novel).

it is still very possible that it is Kyon who is the godlike being
or that he imagines all this that happens and that he brings in cute girls in his fantasies and so on

so...he might be the most powerful being of all these that have been mentioned

angel densetsu is about a guy that when he transfers school ends up with delinquents and martial artists

Ok, but then every of his examples are wrong for the same reason


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What I like in Trivial Pursuit style. Pick your category:

if u are really looking for normal guy surrounded by extraordinary characters:
keiichi in ah! my goddess fit perfectly... he got no superpower or magic or special ability.. just your average mechanic surrounded by multiple powerful goddesses and demons.. but if u say that he is worthless character, bell will make you take it back and he will prove you wrong ^__^
and maybe to love-ru