Grunts are Covenant "cannon fodder" according to the books, and make up the bulk of their ground forces. Despite their all-too-often retreats in Halo 1, the novels describe them as almost heroic in their persistence. In Halo 1, Grunts wielded plasma pistols or needlers, and often carried plasma grenades. SpecOps grunts, wearing black uniforms, also carried Fuel Rod Guns similar to those that Hunters have molded into their arms and the alternate firing mode for the Banshee. (The Halo PC manual reports them using plasma rifles but not needlers, but I believe this is an error, as I have definitely seen them use needlers but never recall seeing one use a plasma rifle.) Normally grunts are orange or red. Red ones seem to be tougher, and may be Grunts Major, similar to the major/minor divisions seen among Elites and in several kinds of enemies in the Marathon series. Grunts are usually only dangerous in groups, and tend to congregate near stronger units such as Jackals and Elites. The Halo 2 manual indicates that when an Elite is nearby, Grunts are less likely to flee, but will panic when faced by "superior forces".

The insectoid Covenant Drone can fly and uses a variety of weapons. Frankie in particular made mention of them using weapons like the Carbine and sniping from high areas, but advised players to attack them in the air because they're even more dangerous when on the ground. Weapons with recoil, like the SMG and the battle rifle, are expected to be more effective than others against drones because the recoil will help track overflying units. The Halo 2 manual refers to Drones' ability to fly as "limited", relying on anti-gravity assistance, but also says they use this ability to gain an "almost insurmountable strategic advantage." Thanks to BOLL who extracted the image from Halo2.com.

The Elite Major, or red Elite, is the strongest type of normal Elite, excluding camoflauged Elites, which are normally weaker, and SpecOps (black) Elites, which are usually stronger. The Major/Minor nomenclature continues the tradition from the Marathon series.

This maskless Grunt is probably in a methane environment, hence no need for an air mask.