Sharpened Darts Lab is a SupportMonkeycard in Bloons Card Storm, introduced in version 4.0. It is temporary and instead of being able to attack, each time the player plays a Primary Monkey, it consumes 1 ammo and causes that Monkey to attack a random enemy Bloon, without consuming its ammo. These attacks occur in order of when they were placed. The attack triggers before receiving any ATK modifiers, such as from other Monkeys (e.g. Dart Monkey Twins or Monkey Village) or game rules (e.g. Game Night). The attack inherits any bonuses that Monkey has (e.g. Spike-o-Pult's scaling per pop, Missile Launcher's double attack, Sharp Shooter's first shot bonus). The Sharpened Darts Lab's ammo can still be used if opponent has no Bloons on their side.
The card artwork depicts a Dart Monkey inside a training zone with many darts, the monkey delightfully holding an enhanced dart, with the Sharpening Darts building at the back of the enclosed wooden fencing. Many darts are stuck onto various surfaces, including the ground, straw Bloons, and a bullseye target.
For its price, it's fairly strong as a secondary source of damage, provided Primary Monkeys with high Attack Power are used. Because it falls off later in the game, use it with an aggressive loadout.
Bomb Shooter is a cheap but efficient choice. Bomb Bloon's bonus Bomb Shooters synergizes with this dual combo.
Because Sharpened Darts Lab is affected by the card effects of Primary Monkeys, Sharp Shooter and Missile Launcher are good candidates for the high damage. So is Frag Bomb Shooter if there's many Bloons, Bloon Impact for support with Heroes that can't grant extra ammo, or Spike-o-Pult to potentially gain a headstart.
Its cheap cost allows it to be functional support during the early-game. Try to draw this card early with another Primary Monkey, as it is bad alone.
During the Version 5.2 playtest, Ninja Kiwi proposed a buff to Sharpened Darts Lab by decreasing its Gold cost from 2 to 1, which was left unchanged for the update.