Games Like 9SHOT

This game is purely for catharsis; there's no main storyline and it will never conclude.
"9Shot" is a first-person shooter game set in a zombie-infested Tokyo streets . Your objective is simple: survive against waves of zombies for as long as possible. Earn points by killing zombies to upgrade weapons

Endless Zombie Onslaught
Experience relentless zombie spawns in a time-unlimited game mode, where the frequency of zombie appearances progressively increases until players can no longer endure.

Infinite Weapon Upgrades
Score points by slaying zombies to continuously upgrade your weapon's abilities, with no limit to their potential