Pre-Emptive is an attack behaviour characterized by an attack that only affects bloons that enter the screen. It is part of the damage types family. Bloons that are already onscreen during the attack, and the descendants thereof, are ignored. This is the opposite of most attacks, which can only affect bloons that have already spawned. It was first introduced in Bloons TD 5 with the introduction of the Ninja Monkey's Sabotage Supply Lines upgrade, which only affected incoming bloons.
Pre-Emptive is represented on Bloons Wiki as 
, the upgrade icon for Pre-Emptive Strike, whose pre-emptive missiles target MOAB-Class Bloons entering the screen.
Typical examples of Pre-Emptive behaviour include Pre-Emptive Strike missiles, Benjamin's skimming and Syphon Funding abilities, and Grand Saboteur ability's 25% HP reduction.
List of Towers and Upgrades with Pre-Emptive behaviour[]
BTD5[]
BTD6[]
Tower:
Heroes:
- Benjamin's skimming and Syphon Funding abilities
Bloons Pop![]
- Dr. Monkey's Shield Remover (Party Crashers only), as it is applied outside of levels, thus applies to all bloons in levels where this bonus is active
