A devastating missile strike on the largest bloon on screen. Destroys up to a ZOMG bloon in one go, or many lesser bloons.
~ Official description
First Strike Capability is the final Path 2 upgrade for the Monkey Sub in BTD5. In BTD5, it costs $17000 on Easy, $20000 on Medium, and $21600 on Hard and $24000 on Impoppable. In BTD5, it is the only ability that is capable of taking out a whole Z.O.M.G. in one strike. The player must be rank 49 to use this upgrade, while on flash version this upgrade has been already unlocked, even before the Monkey Sub is unlocked. When activated, the submarine fires a missile at the strongest bloon on screen.
When it comes to Z.O.M.G. destruction, this tower can destroy a single ZOMG even faster than a max Temple of the Monkey God due to the ability. Against groups of ZOMGs, though, the max Temple is far superior because unlike the First Strike Capability, it can deal enough damage per second to quickly take down even groups of ZOMGs without activated abilities.
Also worth noting is the ability can only take down 1 ZOMG at a time. Any ZOMGs that are hit with the splash damage of the missile will be reduced to 4 BFBs.
This ability will prioritize its targets by strength but will spread its fire to the second after the first is destroyed and so on.
During the Cold War, when the United States and the Soviet Union were preparing for nuclear war against each other, the nation that fired its missiles first was said to have dealt the "first strike" and would be much readier to receive missiles from the other side, giving their population a huge advantage. Additionally, both the US and the USSR deployed nuclear submarines, which the BTD submarine resembles when carrying this ability; some of these submarines could carry nuclear missiles which would have an impact in the greater nuclear exchange.
It resembles a U-boat, a German submarine used in World War II
Because of the Monkey's headgear, it is most likely that it was meant to be the Typhoon-Class Red October.
The monkey piloting the submarine resembles Sean Connery acting as Marko Ramius in "The Hunt for Red October". Like the actor, the monkey wears a black ushanka and has a white beard.
Fittingly enough, Red October was a nuclear-capable submarine.
First Strike Capability can destroy 1 ZOMG, 5 BFBs, or 26 MOABs in one go.
In BTD5 Flash, it can destroy 1 ZOMG, 6 BFBs, or 28 MOABs.
The Technological Terror's Bloon Annihilation Ability is more effective at destroying Packed MOABs or Packed BFBs than the First Strike Capability Ability is; however, the First Strike Capability Ability is better at destroying a single ZOMG than a Tech Terror can at destroying on ZOMG plus the ability.
In the submarine rescue mission in BMC, the submarine situated at the end of the track is a Monkey Sub upgraded with First Strike Capability. The player can repair it for 8000 battle funds.
The ability in BTD Battles cannot destroy the ZOMG on Round 43 due to MOAB-Class health being upgraded after Round 32. It can destroy a sent ZOMG on Round 31 and below though.
In fact, a single First Strike cannot even pop the outer layer of the Round 43 ZOMG, as this layer has 23200 HP.