Type-33 needler

Stats Rate of fire: Average to high (3-10 per second, increases  with continued fire) Damage per hit: Low to very high (Explosion will occur per 7  needles in target) Range: Short to medium (most effective at short range) Accuracy: High (Needles are homing) Magazine size: 20 needles (30 in Halo 2) Maximum ammo: 90 needles (including fully loaded magazine)

Advantages
This weapon fires tracking needles that embed themselves in the flesh of a target. Rate of fire increases with continuous fire, up to 20 rounds in 2 seconds (one complete clip). If 7 or more needles accumulate in the target, an explosion will occur, causing small splash damage. Needles can penetrate the energy shields of Elites/Sentinels/Spartans (and the Master Chief), but they bounce off the hand-held shields of Jackals and Hunters.

Disadvantages
The needles are slow, and are not effective against vehicles. The needles also take time to hit/explode on the target, leaving the target time to move in and cause some of the explosion to damage the shooter. It is nearly impossible to hit invisible Elites with the Needler, as they do not home to camouflaged targets. While shooting Flood with it may be effective, they can often come close enough to damage the player with the splash damage from the explosion, due to Flood forms' speed.

Influence
The needler was inspired by the Flechette gun from the Marathon series.

Multiplayer Role
The needler is an all-purpose weapon, particularly useful for annoying opponents with heavy weapons, since the needles discharge before the opponent can home in on the target. Also, the fact that the needles home onto target make it a good weapon when riding shotgun on the Warthog, as the Warthog's motion makes aiming difficult. However, the opponent can dodge these needles by hiding behind cover, so this weapon is best used in large open areas. The Needler is also highly effective against long-range or hard-to-see enemies; merely point in the general direction of your opponent, and the needles will home in on the target.

Effective Against
Elites, Grunts, Brutes, Sentinels, small groups of tightly packed Flood.