Marathon Man

Marathon Man is a Halo 3 Achievement. It is awarded for accessing all the Terminals in Campaign mode.

The achievement awards the player 40 Gamerpoints.

It is represented by a yellow circle with a person whose head has a Marathon symbol on it, and with seven yellow stars (representing the seven Terminals) above him.

The achievement can be completed on any difficulty.

It is similar to the Marathon: Durandal achievement, Hats off to 819.

The award itself is a reference to Marathon (video game series) as you could access Terminals in game to gather information on the Marathon universe. Details:
 * After you access the terminal, you need to wait for the screen to go red then wait until the screen shows another text message and finally press A to scroll down to the very last message (a fragment from a Forerunner message) to show up to get the achievement.
 * To access the terminal you must "flip" through the terminal until it redirects you then you flip through the last pages, then wait a few seconds for the screen to turn red and another fraction of message to show, then leave.
 * For some players, the achievement will only be unlocked if the seventh terminal is accessed last.
 * A player must access seven terminals, another seven reference (there is an additional eighth one on Cortana, but this isn't necessary for the achievement).

Trivia

 * Marathon is the name of an earlier series of Bungie games (Marathon, Marathon 2: Durandal, & Marathon Infinity)
 * Marathon Man was a movie made in 1976.
 * There are seven stars, one for each terminal, on the Achievement picture, a reference to the number 7, Bungie's favorite number.
 * The person on the medal has a Marathon logo for a head, a reference for the Marathon game.
 * In the Marathon game series, terminals were integral parts of the campaign levels: They functioned both for providing storyline, guiding the player, and transporting the player to the next level. They are integral in Halo 3 to learn the downfall of the Forerunner in their battles against the Flood.
 * While there are technically only 7 terminals, a distinctive 8th terminal can be found in Cortana (Level), where the Gravity Hammer is located.
 * In the Nintendo game Super Smash Bros. Melee, you would receive a reward of the same name if you ran much more than you walked.
 * Marathon Man is very similar to Halo 3: ODST's Audiophile Achievement.

Internal

 * Halo 3 Achievements
 * Terminals