Operation: Dart Storm

 is the final upgrade for Monkey Ace in BTD4 and the third upgrade on the second path in BTD5. It allows the ace to shoot faster and shoots out 16 darts with each shot instead of 8. It will also drop Pineapples at faster rates (in BTD4 only). It is very useful for thinning out a large number of bloons during the later Rounds.

Trivia

 * The name of the upgrade is likely to be a spinoff from Operation: Desert Storm.
 * The plane looks similar to the B-2 Spirit Bomber.
 * In Bloons TD 5 instead of the B-2 Spirit, the plane looks like a F-117 Nighthawk. This makes it more fitting as F-117s were actually used in Desert Storm.
 * When using the Supply Drop Ability, a plane similar to the Operation: Dart Storm (albeit slightly darker) will come and drop a crate containing $500 – $1500.
 * It is just as effective as one of the planes launched by the Aircraft Carrier.
 * This is less powerful in BTD5 than it is in BTD4.
 * They can beat the M.O.A.B. Challenge in BTD4 easily.
 * There is a bug in BTD5 where the Monkey Ace, when upgraded to this, would always face to the right of the screen.
 * In the DSi version of BTD4, if there are enough bloons on screen, the Monkey Ace will drop 2 Pineapples every second.
 * It is revealed in Bloons Super Monkey 2 that the designation for the plane is B12.
 * The description for Operation: Dart Storm in BTD4 is a reference to a quote in the movie 300. The 300 quote, "Our arrows will block out the sun.", is nearly identical to the upgrade description, replacing arrows with darts.