Indie:

Covenant

 Grunts - Unggoy

• Orange Armor - Grunt Minor
• Red Armor – Grunt Major
• Green Armor – Grunt Heavy Weapons Specialist
• Black Armor – Grunt Special Operations
• White Armor – Grunt Engineer and Special Operations Commando

Drones - Yanme'e

• No Known Ranking System

Jackals - Kig-Yar

• Blue Shield – Jackal Minor
• Orange Shield – Jackal Major
• No Shield – Jackal Sniper

Hunters - Lekgolo

• No Known Ranking System

Engineers - Huragok

• No Known Ranking System

Brutes - Jiralhanae

• Brute without Helmet – Brute Minor
• Brute with Helmet – Brute Major
• Brute with Helmet and Flag – Brute Captain
• Brute with Honor Guard Helmet – Brute Honor Guard
• Brute with Honor Guard Helmet and Flag – Brute Honor Guard Captain
• Brute with Fist of Rukt Hammer – Brute Chieftain

Elites - Sangheili

• Blue Armor – Elite Minor
• Red Armor – Elite Major
• Cyan Armor with Jetpack – Elite Ranger
• Chrome Armor - Elite Stealth Commando/Osoona (Halo: CE)
• Gray/Brown Armor - Elite Stealth Commando/Osoona (Halo 2)
• Black Armor - Elite Special Operations Commando (Halo:CE)
• Violet Armor – Elite Special Operations (Halo 2)
• White Armor – Elite Ultra
• Gold Armor – Field Master/Ship Master/Fleet Master/Zealot
• Crimson Ornate Armor – Elite Honor Guard
• White Ornate Armor – Elite Ultra Honor Guard
• White Ornate Armor with Ornate Headpiece – Elite Honor Guard Supreme Commander
• Violet Armor and Cloak – Supreme Commander ^[1]
• White Armor with Ornate Headpiece – Elite Councilor
• Gray Ornate Armor – Arbiter

Prophets

• Minor Prophet/Legate - Minor Prophets command ships and conduct research on Forerunner technology and artifacts. It is presumed that they command the Engineers.
• Prophet Councilor - Prophet Councilors sit on the Council of Concordance and speak on behalf of the Prophets and the religious interests of the Covenant.
• Prophet Hierarch - Three Prophet Hierarchs assume total control over the Covenant.
  • Prophet of Truth - Hierarch of the Covenant
  • Prophet of Mercy - Hierarch of the Covenant
  • Prophet of Regret - Hierarch of the Covenant

 

and thats just the possible covenant troops...this isnt even vehicles or weapons

Nice find, Indie. I didn't realize the diversity and unit class in the games. Even though you copy-pasted it directly from the wiki entry without even removing the link reference, it's still a nice find.