Archer Missiles are secondary weapons mounted on all UNSC combat vessels.
Tipped with high explosive warheads, electronically guided and stored in pods, they are fired in salvos and provide a steady stream of damage.
Guided missiles predated magnetic accelerator cannons, or "MACs" as the primary armament on human warships. With the advent of MACs they have been relegated to the role of secondary armaments but are still reliable at dealing steady damage to the enemy while the MACs recharge.
Prior to the Human-Covenant War, the UNSC found these missiles to be effective against human vessels such as Insurrectionist-controlled ships. Against the Covenant, however, they realized that the defensive measures employed by the enemy ships such as energy shields suddenly rendered Archer missiles near-obsolete. Tactics were developed to counter this, using the more devastating but slower-firing MACs to break through the shields, rendering the hulls vulnerable, but on the whole, Archers proved to be ineffective weapons against the Covenant.
These missiles are fired in large volumes and contribute to Phase Two in engagements.
Archer missile pods fire more frequently than MACs, each mounted pod firing once per volley, and several volleys can be fired before a second MAC shot is fired. However, they deal low damage to shielding and low damage overalll. They can be fired at targets not directly in front of the ship, however, and will continue to target an enemy ship even after the ship that fired them is destroyed. Many upgrades exist to increase their damage and range.
Larger ships will carry more and more pods, allowing for higher damage output per second than smaller ones. The Gladius-class corvette, the smallest UNSC ship with Archers, mounts only two pods while super capital ships like the Epoch-class heavy carrier mount dozens and dozens.
The Hillsborough-class light destroyer's Archer missiles can be replaced with Ares missiles, carrying powerful concussive warheads that have just over twice the damage per shot and inflict a small weapons cooldown debuff to the target. This is tailored to meet the ship's focus on damage per second as opposed to outright damage, like its cousin the Halberd-class destroyer with its improved twin MACs.