Arrival

Arsenal is the first level of Halo 3. It contains no actual gameplay, consisting instead of a tutorial (on lower difficulties) and the game's opening cutscene.

Plot
The level consists solely of the game's opening cutscene and the tutorial.

Transcript
Cutscene A night sky. Cortana (V.O.): "They let me pick." {pause} Cortana (V.O.): "Did I ever tell you that?" {pause} Cortana (V.O.): "Choose whichever Spartan I wanted." {pause} Cortana (V.O.): "You know me. I did my research. Watched as you became the soldier we needed you to be. As the camera pans down, something comes into view. A fireball, splitting the night sky, leaving a trail of flame and smoke in the atmosphere. Cortana (V.O.): "Like the others, you were strong and swift and brave. A natural leader." The fireball comes nearer, at an oblique angle to the camera. Cortana (V.O.): "But you had something they didn't. Something no one saw..." A second, lesser fireball breaks off from the main one. It moves at an oblique angle to the first, which is to say, towards the camera. Cortana (V.O.): "...but me." The second object moves nearer. The first vanishes behind a spray of trees. Cortana (V.O.): "Can you guess?" The object moves even nearer, and its trajectory begins to curve until it is heading directly for the camera. Cortana (V.O.): "Luck." The fireball roars past the camera and smashes into the ground with an earth-shattering impact. For a moment, we can see that the area is a jungle, quiet and peaceful, and now, full of light and sound. Cortana (V.O.): "Was I wrong?" {fade to black} Pan down on the same forest, but now, it's early morning, with the sun streaming through the trees onto the smoking ruin where the object hit ground. In the foreground, an armored gauntlet is visible. In the background, several Marines move around. The one in the back wears a sergeant's cap.'' Marine 1: "This ain't good. Damn." Marine 2: "How far did he fall?" The Sergeant in the hat turns around and takes a long drag on his cigar. Marine 3: "Two kilometers, easy." ''The Sergeant blows out smoke. It is none other than Johnson.'' Johnson: "Stay sharp." ''The Marines move closer to the object. For the first time, we can see that it is the Master Chief. He lies at one end of his own personal crater...the results of falling two kilometers, apparently. The MJOLNIR armor's designers would be proud. Despite the motionlessness of the man inside, the armor is neither scratched nor singed. The Marines move closer to the Chief, taking up combat positions. One sits down beside the Spartan and takes out a small computer. Johnson: "Corpsman?" Marine 3: "His armor's locked up. Gel layer could have taken most of the impact." ''He taps something in on the computer. The Chief's outstretched arms collapse onto his chest.'' Marine 3: "I don't know, Sergeant Major." ''The Sarge kneels by the Chief and places a hand on his chest, feeling for breath, or any sign that his friend is alive. After a few seconds, he sighs, reaches back, and pulls Cortana's chip out of the Chief's head.'' Johnson: "Radio for [evac?] We're not leaving him here." ''An armored hand reaches up and grabs his wrist. The Chief's voice is almost labored, raspier than ever before.'' John-117: "Yeah. You're not." He pushes himself slowly to his feet. Johnson: "Crazy fool. Why do you always jump? One of these days, you're gonna land on somethin' as stubborn as you are! And I don't do bits and pieces!" ''The Chief says nothing. Instead, he reaches down and takes Cortana's chip from the Sergeant's hand.'' Johnson: "Where is she, Chief? Where is Cortana?" The Chief stares at the data crystal, and for a second, Cortana's face flashes across the screen. Cortana (V.O.): "Don't make a girl a promise...if you know you can't keep it." The Chief inserts the chip into the plugin at the back of his head. John-117: "She stayed behind." Johnson: "Corporal, make it quick." Marine 3: "Sorry, sir. {to Chief} Your armor's still in partial lockdown." {The "look around, move around, charge your shields" tutorial takes place here.} ''The Chief looks around, taking in his surroundings. Somewhere near him is a familiar sight...the heat-wave effect of a Covenant active camouflage. The Chief moves with fluid grace. Brushing aside Johnson and another Marine, he grabs a pistol and jams it between the mandibles of the decloaking Elite.'' Johnson: "Chief, wait! The Arbiter's with us!" The Arbiter glares at the Chief, who hesitates to lower his gun. Johnson: "Come on now. We got enough to worry about without you two tryin' to kill each other." ''He grabs the Chief's shoulder. The Spartan lowers his gun. The Arbiter clacks his mandibles together--a shrug.'' Arbiter: "Were it so easy..." ''He makes as if to push past the Chief, but the Spartan stands his ground. They do not speak, but an wordless conversation passes between them:'' I don't trust you. The Arbiter turns and walks away. Arbiter: "We must go. The Brutes have our scent." Johnson: "They must love the smell of badass." ''He grabs an assault rifle and holds it out to the Chief. Angrily, the Spartan grabs it by the pistol-grip.''