The temple is a cultural and scientific Covenant structure featured in Halo Wars. This is where the Prophets meditate and study Forerunner artifacts and make battle plans against humans. It also houses other characters of importance including the Arbiter and the Brute Army Commander.
In the temple, the player can upgrade units and buildings. These upgrades are very expensive, but very effective and powerful. All Plasma turrets surrounding the Citadel can be upgraded from small to medium or large. Max population of the player's army can be increased by 10. All Covenant Shields can be upgraded to make them recharge faster. You may also upgrade your leaders. The Temple could be said to be equal to a UNSC Reactor and Field Armory.
Covenant hero units can be retrained if they are killed, and their abilities can be enhanced inside the temple as well.
The most important function of a temple is its ability to advance the player's "Age", which means increasing the player's technology. The first Age is the one the player starts with after the Temple has been built, the second Age is the Age of Doubt, and the Third Age is the Age of Reclamation. Some units, such as Scarabs, are only available during the Age of Reclamation. Since the Temple is so important, the player should place it at the rear of the Citadel, surrounded by turrets.
If the temple is destroyed, the technology level returns to zero, however, it can be restored to its previous level if another Temple is built. Once a temple is built, a Leader unit appears on the battlefield. Players are allowed to have only one temple at a time.
- The name is a probable reference to Ensemble's previous game installment: Age of Mythology, where a Temple can be built to train Myth Units.
- As seen in the temple image, the temple changes its appearance with each Age.
 List of appearances
- Halo Wars (First appearance)