• Whenever a bullet hits an enemy or wall, or reaches its maximum range, it splits into several smaller, lower-damage bullets that travel outwards within a limited range.
• Doubles the damage of Beam style Guns .

• Anti-Aircraft - If the player has [RPG] , it spawns seven homing flak bullets on impact. This synergy causes all flak spawned while [RPG] is held to become homing, most evident by the shots of familiars.
• Piercing bullets will not split when hitting enemies, but will split when hitting a wall or reaching their maximum range.
• Different weapons have their bullets split into different numbers of smaller bullets, and the smaller bullets do varying amounts of damage. For example, the [Marine Sidearm] splits into 4 bullets, the [Dungeon Eagle] splits into 3, and the [Winchester Rifle] splits into 7.
• The damage of each smaller bullet is equal to the damage of the original bullet divided by the number of split bullets.
• The beam damage multiplier granted by Flak Bullets does not stack with the beam damage multipliers of [Shock Rounds] , [Katana Bullets] , [Explosive Rounds] , [Shadow Bullets] , [Vorpal Bullets] , [Blank Bullets] , [Devolver Rounds] or [Hungry Bullets] .
• Flak Bullets makes [Casey] fire three high-damage bullets when swung. This is due to the fact that Flak Bullets have a set range, while [Casey] normally shoots an invisible bullet with near-zero range. Whether this was intentional or not is unknown.
• Reflecting any enemy bullets with [Casey] causes the bullets reflected to split into multiple enemy bullets.
• The [Shock Rounds] -like chaining effect will not appear with child projectiles fired from the [VertebraeK-47] .
• Flak Bullets makes [Alien Engine] rapidly fire bullets when fired. The reason for this phenomenon is the same as for [Casey] .
• Flak Bullets does work with most beam weapons.
• Flak Bullets causes [Boxing Glove] to fire bullets in a relatively wide spread, and the reason for this is the same as [Casey] .
• If two copies of Flak Bullets are acquired through modding, luck or through the double item chest glitch , the smaller bullets will continuously split into more bullets. This continues until the game crashes or the extra copy of Flak Bullets is dropped.
• With [Face Melter] , bullets that come out of the amplifier will turn into default-looking bullets when splitting.
• Flak Bullets will overwrite the Terminated, Too synergy on the [Grenade Launcher] . At least, this is true if the synergy comes from [Lich's Eye Bullets] .

Purchase from Doug for 28 .