All grunts. All the time. Aim for the face.
Gruntpocalypse is similar to the Bonus Round featured in Halo 3: ODST Firefight. As such, it involves a massive army of Unggoy of various ranks that will spawn in waves. There are no drop-ships; in wave-to-wave, they spawn in random places, making the game less time consuming. This can be changed in Settings, however.
In the Score Attack Matchmaking playlist, the gametype consists of an average of 120 Grunts that spawn in 5 waves, with the Catch skull, the custom Red Skull which enhances sight, aim and hearing, the Grunt Birthday Party skull, and the Cloud skull.
- In Halo: Reach, Gruntpocalypse is regarded as one of the best and easiest ways to earn a high amount of cR over a relatively short period of time.
- The achievement, Score Attack (earn 15,000 points in a single match), is easiest to unlock on this gametype.
- Grunts in this mode are much less likely to run away when injured. However, they will still run if their leaders and allies fall beside them.
- The game type is deceptively difficult on higher difficulties such as Heroic or Legendary, since Ultras and Spec Ops do not spawn on lower difficulties. This can make you throw caution to the wind, allowing them to stick you with multiple Plasma Grenades.
- Most squads usually have one Specialist Unggoy; however, sometimes Specialists do not appear at all in a wave.
- The most dangerous Grunts are the Grunt Specialists carrying Fuel Rod Guns, as they can kill you very quickly.
- Using Armor Lock is highly recommended, as this can protect you from Fuel Rod Gun blasts, Plasma Grenades, and Plasma Pistol overcharge shots. However, this cannot be entirely reliable, as activating Armor Lock occasionally prompts the Grunts to toss more Plasma Grenades, which may ultimately kill you once the lock limit is reached.
- This is an easy way to upgrade the "Dome Inspector" commendation relatively quickly.
- Despite the name and description, Grunts are not the only enemies you face, as if you activate Hazards in the firefight options menu drop pods containing Brutes armed with Spikers, Gravity hammers and Concussion rifles as well as Elite Ultras armed with Plasma repeaters drop into the fight.