Bloon Area Denial System (or B.A.D.S for short) is the final upgrade of Path 2 for the Dartling Gun in BTD5. It costs $17000 on Easy, $20000 on Medium, $21600 on Hard, and $24000 on Impoppable. It enables the Dartling Gun to fire 3 hydra rockets instead of one at a time, spread out in a conical formation allowing the Dartling Gun to pop many more bloons.
Purchasing this upgrade also enables use of the Rocket Storm Ability, which when activated, shoots out up to 100 missiles towards the nearest 100 bloons (all bloons on screen if less than 100) on the screen every 2 seconds for five times.
The Rocket Storm ability is much less effective in the Mobile/Steam version than in the Flash version. Instead of firing up to 100 missiles toward the nearest bloon on the screen it only fires one missile toward the nearest 100 bloons on the screen.