Action anime where MC isint afraid to kill..?

I'll continue

Mahouka Kouko No Rettousei

Mondaiji-tachi ga Isekai kara Kuru Sou Desu yo?

Maoyu Maou Yuusha

To Aru Majutsu No Index

Trigun

Campione

Darker Than Black

Tears To Tiara

Needless

Kiseijuu: Sei no Kakuritsu

Kure-nai

Koutetsujou no Kabaneri

Hidan no Aria, maybe i think? kinda forgot already

Akame Ga Kill

Gate: Jieitai Kanochi nite, Kaku Tatakaeri

Dungeon ni Deai wo Motomeru no wa Machigatteiru Darou ka

Black Bullet

Grisaia no Kajitsu/Meikyuu/Rakuen

Gintama

Baccano!

Hellsing Ultimate

Samurai Champloo

Katanagatari

Full Metal Panic

Berserk

Kaze no Stigma

One Punch Man, right?

Zetman

oh and i should say Kirito from SAO don't like to kill real players only the enemy inside the game.

Bleach

Code geass

Naruto/shippuden

Attack on titan

Fate stay night/Fate zero/UBW

Gungrave

Akame ga kill

Parasyte

Trinity blood

Blood +

Gunslinger girl

Claymore

Shiki

Death note

Samurai champloo

Inuyasha

Rurouni kenshin

Yu yu hakusho

Deadman wonderland

Black lagoon

Jormungand

Casshern sins

Ikki tousen

Guilty crown

SAO

Blue exorcist

Tokyo ghoul

Akame ga Kill

Black Lagoon

Jormungand