Power increases the damage of each bullet.

Number of magazines increases the maximum number of magazines.

Hit ratio increases head hit ratio (aiming circle should still be within the effective range of standard head)

Changing the speed shortens the time to change the clip.

The recoil decreases and the speed of the aiming circle increases after shooting.

The order may be wrong, but it is probably these five items. Different guns have different functions:

The number of machine gun magazines has been upgraded a lot. With the time of changing orders, you can shoot at the big shots, and you can bite the bullet and hit them straight. It is suitable for a large number of zombies fighting with boss in medium and long distance, and machine gun bullets are also the easiest to obtain and save.

The shotgun is the most powerful, but the range must be very close. After a large number of others approach, it will spray hard, small and many enemies.

Crossbow, I forgot what gun there is. The crossbow is almost single shot, the number is very small, and it is difficult to hit.

Knife, don't forget this artifact. Killing leeches is very effective. You can kill them with one shot.