I'm looking for mangas which have/had the best MC introduction (so the first time the readers gets to see the MC)
I'd prefer action mangas where the MC enters the scene end everyone is like 'woah that guy is badass" or something like that.


This scene could also happen after a time skip in the story. I'm also okay with those.

i'd say the best for me would either one piece or beelzebub

Onepunch-man definitely

There is nothing on par with Maria's introduction in Hakomari.
Another famous introduction is Haruhi in Suzumiya Haruhi no Yuuutsu.

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

this one definitely...

usual shounen with strong MC often use that kind of entrance, such as when Luffy start his adventure in One Piece or when Sena play american football for the first time in Eyeshield 21.

Other than MC, I really felt intimidated when MC's father in Vinland Saga take action.
He IS the definition of badass...

Shin Angyo Onshi has one of the best MC introduction!

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Your drill is the drill that will pierce the Heavens!

BERSERK
blood bath

When i read "Best first main character introduction/entrance" i come here thinking exactly that.

Senjougahara Hitagi of the Monogatari (Novel) series leaves you with warm fuzzies when she introduces herself.

Second Hakomari.

The seinen series Dorohedoro where the MC bites other people's heads to find out who he is. But yeah, it has one of the best/funniest MC intro in manga history