Drinol

The Drinol are Covenant beasts that did not make it into Halo 2, and it is unknown if they will be seen in future products of the Halo universe.

In the Behind the Scenes DVD, Drinol are described as huge beasts that are kept contained and segregated from the other forces. Possessing phenomenal strength, they are used to smash enemy vehicles.

They have not made the final cut in any of the games. However, it may have inspired a Flood form from Halo 3 known as a Flood Tank Form. The appearance is similar but the Tank has a hollowed stomach and is a darker tan color. They perform the same job as they did in Marathon, strong, slow moving creatures. They even have a similar growl which indeed sounds like "drinniol". The Tank Form is even stronger as it can take a player out in a single swing from its mighty arms on Heroic, using the same tactics as the Flood tank forms. They are nowhere near as resilient as their Drinol concepts, however, and are especially vulnerable to plasma and fire-based weapons. It is unknown if the Drinol was to have a similar weak point, or if it would just be a damage sponge.

They could have also inspired the Flood Juggernaut which was in the game code for Halo 2 but was removed half way through. Bungie probably wasn't ready to reveal the Drinol yet, so that's why they removed the Flood Juggernaut from Halo 2's game code.

It was possible that it could have been a replacement for the Hunters in the Covenant Loyalist military in Halo 3, but was instead scrapped for the Hunter to keep players from being confused about which alien was with which faction.


 * --Gamesradar article

Marathon Connection
Bungie enjoys placing links to their previous game franchise Marathon into Halo.

From a description of an enemy in Marathon:

They appeared in two levels in Marathon, and seem to be slow as mentioned above but also unintelligent, with spike-like organs on its skin.