A new Augment system comes to the Zombies mode of Call of Duty: Black Ops 6, with Ammo Mods being one of the three types you can unlock. Along with Field Upgrades and Perks, Ammo Mods provide passive buffs that can help you survive undead waves as they get tougher. Ammo Mods change what bullets your weapon fires, adding new effects or elemental damage against your enemies.