To see Grunt Aerobics on Assault on the Control Room, grab the Banshee earlier than usual. From here, you can finish the level without having to open the big doors at the end or fight hordes of Covenant forces. Just park your Banshee backwards, so that the front is facing toward the ramp leading to the top. Once it is backed up as far against the door as it will go, get out. The Banshee should push you through the door, where all of the enemies should be frozen (since the door was never opened). The only things that move are little circles of Grunts that jump up and down in sync, one after the other.
You can also do this with a Ghost, by strafing to the right towards the door and getting out of the Ghost so that you are out just before it hits the door. This method is easier than the Banshee method.
This strange Grunt behavior can be witnessed in the Pillar of Autumn on any difficulty—when you reach the point that there is a long hallway with a couple of Grunts at the end (it has some Bumblebee life boat docks at the side).
They can also be seen on the The Silent Cartographer, when you come out of the security building and look over at the Grunts on top of the ridge in between the ocean. Take out your M6D pistol and zoom in on them, but don't shoot them, as they will start jumping in the same way as in the fifth level.
- Similar behavior can be witnessed on the Halo 2 level, The Arbiter, when played on Legendary. The Grunts are seen dancing in synchronization around the Grunt Birthday Party Skull.
- First they shake their hips; then, after a few seconds, they usually jump up and down.
- Some Grunts in Halo 2 and Halo 3 will do this; however, it is very rare.
- Sometimes the Grunts will get in their crawl-walk (on their feet and free hand) then stand up, shake their hips, and jump.