Exterminator is a meta-game achievement in Halo 3 and Halo: The Master Chief Collection. It is earned when the player scores 15,000 points while playing the meta-game on Floodgate. This Achievement awards the player 10 Gamerpoints.
It is represented by a blue circle with a horned medieval helmet, also known as the "Warrior" emblem. The level is aptly named, because it is the first level to feature the Flood in Halo 3, and it lets the player "exterminate" them. This is most likely one of the most difficult levels to score 15,000 points in, as it is the shortest level, and the Arbiter and Elites can steal valuable points.
The Catch Skull has no effect on the Flood as they don't throw grenades, but the Marines and Elites are affected by it, and are likely to stick you if you have this skull activated. Because this skull will not make the Flood any more dangerous in this level, activating it is a good way to multiply your points a little more. Also, because the level is relatively short, it would be a good idea for the player to complete the mission within a short period of time, as point multipliers can be gained at the end of the mission based on the total amount of time the player takes to complete it. Another strategy is to either kill or rush ahead of your allies, but this can be troublesome, especially if the Arbiter turns against you.
- Activate the Tough Luck, Catch and Fog. If you wish, activate the Black Eye skull, but at your own risk (the Black Eye skull's effect is that your energy shield will not recharge unless you perform a melee hit). Another strategy would be to use the Flamethrower to take out as many Pure Forms as possible.
- If you wish to unlock the achievement on Normal, activate the Thunderstorm, Tough Luck, Famine, Catch and Cowbell skulls.