ForgottenLife
Only gun type weapons not sword type ? ......... I mean DMC Vergil dark slayer style with yamato. It can cut even space febric so mc can travel like sasuke do with help of his eye.or sword technique from Demon slayer ( sun breath, thunder breath ,water breath ....) Or Haki power from one pice(if you can it must) If want fighting style then from one punch man water stream rock smashing fist , whirlwind iron cutting fist or from God of highschool Renewal Taekwondo. And if you want to give him eye type power then from "Blood Blockade Battlefront" All Seeing Eye of God.