Ammunition in Diep.io are the weapons that can be created or controlled by the player to attack other players. Players cannot gain experience by destroying ammunition, but it will damage their tanks upon contact with any. Ammunition includes Bullets, Drones, & Traps. The only tanks that do not use ammunition are the Smasher and two of its upgrades; the Landmine and the Spike.
Bullets come in varying sizes depending upon the type of the Tank employing them. Though their speed and strength vary, their lifespan is always the same, and they will expire after a set period of time.
These also come in differing varieties. Generally speaking, Drones are triangular, fast, and strong, typically used by Overlords and Managers. Unlike bullets or traps, they have unlimited lifespan, with the only exception being Battleship's Partisans. Beyond that, there are three variations: Undead, Partisans, and Minions. Undead are used by Necromancers and are slower but more numerous, whereas Partisans are used by Battleships and are both faster and more numerous, but much weaker. Minions vary the greatest from other types of Drones, being small, controllable Tanks in their own right which accompany Factories.
Traps are small, immobile mines that are used by Trappers that deal damage to Tanks coming into contact with them. While lifespans differ traps have a significantly higher lifespan than bullets. There are only two variations of Traps: a slightly larger version used by the Gunner Trapper, and a massive version used by the Mega Trapper.