Final Grunt

The Final Grunt (one of the Talking Grunts, often called the "Jerk Store Grunt") is found cowering on the edge of a cliff right before you go down the ramp to leap into the frigate's hanger in the final level of Halo 3. When you're at the top of the ramp leading to the Dawn's hangar, you should be under a rock arch. If you get out while under the arch and face the Dawn, to your right is the Grunt. You should see him. If the player approaches him, he will say:

"Hey, Demon! The jerk store called, and THEY'RE ALL OUT OF YOU! Poor you, stolen at the age of six and conscripted into the military, waaaaaah! ...Okay look, if you let me live, I got the Fist of Rukt. Look, I'll be the bomb. I'll polish your boots. I'll polish your helmet! It's the gas, haha! When I'm on the gas, I don't know what I'm doing half the time!"

However, discovering the "Final Grunt" may leave the player unable to complete the end of the level and the game, because there will be no route available to reach the Forward Unto Dawn since the platforms may have broken if you aren't quick enough. Also note that if you drive up to the Grunt in a Warthog with the Arbiter at the gun, he will shoot and kill the Grunt before you can reach him. Make sure you keep the Grunt out of the Arbiter's line of sight, or the AI Arbiter will kill him.

Trivia

 * The Final Grunt is also known as "The Jerk Store Grunt".
 * The "Jerk Store" joke is a reference to a joke on the American sitcom Seinfeld in which George, one of the four main characters, tries to make a witty comeback at fellow coworker.
 * If you kill this Grunt, it will continue to make its speech. If the Arbiter kills it, it will make its speech. If you kill it while its saying its speech, it will continue. In other words, as long as you come near the Grunt, it will say its speech.
 * This easter egg has a striking relationship with the last level of Halo: Combat Evolved. In the last level, The Maw, it is possible to find another talking Grunt that won't attack, the Thirsty Grunt.
 * "The gas" might actually refers to the methane gas that the Grunts breathe. However this would be unlikely, as they breath it as we breath oxygen. It is more likely he was running out/had run out of methane, and was breathing oxygen and feeling lightheaded.
 * Another explanation could be "the gas" refers to a type of gas that the Brutes possibly added to the Grunts' methane, in order to increase their aggression, as is referenced by a Marine on the level Sierra 117.
 * A third explanation could be that "the gas" is benzene, referred to by Kwassass from Ghosts Of Onyx as "lung gold".
 * While playing the meta-game if you drive close enough for the Arbiter (or a co-op teammate) to shoot and kill him you will not gain the points earned for killing this Grunt. The same goes for other "ambient" AIs e.g. Wounded Marines, crying Marines, Technicians, etc.
 * With the IWHBYD (I Would Have Been Your Daddy) skull on you can hear normal Grunts say this on other levels.
 * Also, if you play on Co-op, the Grunt can talk to the Arbiter, too.
 * The speech refers to when John 117 was kidnapped by the and became a Spartan. Read about this in The Fall of Reach novel.
 * The Final Grunt is the last Covenant foe you meet in Halo 3.
 * Even if only The Arbiter goes up to the Grunt, he/she will still call him Demon, even if the Chief is not there.
 * On rare occasions, after killing the Final Grunt, the player will die for no apparent reason.
 * The Final Grunt does not show up in your radar.
 * With the IWBYD skull on,some grunts might say his 'jerk store' joke to the master chief when thet see him.(you don't have to see the final grunt to hear this).

Related Links

 * Thirsty Grunt
 * Cowardly Grunt