Hunters

Hunters are a race of little orange worms that are a member of the Covenant. They originate from Te, a gas planet that was once inhabited by the Forerunners. The worms has digested the majority of the Forerunner relics on the planet which caused the Covenant to declare war on them.

The war was made very difficult for the Covenant because the worms have the remarkable ability to join up to form much larger fighting machines - Hunters themselves are the names given to bipedal armoured shock troopers of the Covenant that work in pairs - and the Covenant was rapidly losing the war as giant fleshy fighting machines swept through their armies. The Covenant couldn't use their cowardly method of glassing the planet for two reasons - one, it would involve destroying what was left of the Forerunner relics, and two, it was a gas giant and therefore immune to glassing.

So the Covenant were forced to actually THINK of something. Which took them a long time.

They're still thinking.

Still nothing.

Nope.

Nada.

Aha! One day, a particularly smart Elite (who happened to be Arbiter) thought, why is it that there are still some Forerunner relics left after millions of years of worms eating them? It eventually turned out that some worms have bred to eat the metal that Forerunners made all their stuff from, and some have bred to eat everything EXCEPT the Forerunner relics. Although this sounds ludicrous, its what happened. Apparently.

So the Covenant allied with the 'Good' Hunter worms and exterminated the 'Bad' Ones. They suited up the Hunters with Armour and let them loose against their enemies. They even fitted weapons to the massive hunter tanks and called them 'Scarabs'.

During the Covenant Civil War, the majority of the Hunters allied themselves with the Elites, and fought against the Brutes. Smart move.