Legend

Legend is an achievement/trophy in Deus Ex: Human Revolution that is awarded for completing the game on the hardest difficulty level, "Give Me Deus Ex", without changing the difficulty mid-game.

Gameplay changes from previous difficulty

 * Enemies have more health, has better combat A.I and will attempt to suppress and flank the player.


 * Enemies are now more aware of the player's presence:
 * Patrol routes are longer, covering a larger area. Guards have expanded field of view.
 * Enemies becomes hostile easier (upon being detected, seen, heard,...) with longer cooldown time.
 * Less ammunition and consumables are found in the world or are significantly reduced in quantity.


 * Lower level hacks are replaced by advanced hacks earlier in game.

Strategies
Acquiring this achievement is easier than it sounds, as "Give Me Deus Ex" shouldn't be too difficult even for new players, as long as you are cautious and have good coordination. It is best to attempt Foxiest of the Hounds and Pacifist on a Legend playthrough for the recommended stealth tactics.


 * Stealth and non-lethality are crucial, as the enemy A.I are now more aggressive against intrusions. Maintain a low profile at all times. Keep out of sight of cameras and patrols and remember to hide bodies whenever possible.


 * Never attempt any hack that you think can cause an alarm, maximize your hacking skill to prevent hacking failures. Most story related hacks are only around level 3-4.


 * Sneak past enemies as much as possible. If you can, utilize the cloaking aug for better movement inside hostile territory. Do not arouse any alarms/attention to yourself. Try maneuvering large areas behind cover or in vents.


 * Avoid large firefights (Highland Park, crashed VTOL,...) as the opposition can easily overwhelm you. Reduce combat to a minimum. Should combat initiate, immediately take cover and keep an eye out for flanks.


 * Ignore side quests or perform only the ones that do not require infiltrating/hacking/killing.


 * Invest as much Praxis in stealth and hacking as possible. Helpful upgrades such as the Quicksilver Reflex Booster or the Icarus Landing System are highly suggested. The Typhoon Explosive System is handy for ending boss fights quickly, maximize it if needed.

Trivia

 * In earlier builds of Deus Ex: Human Revolution, the full requirement for this achievement to unlock is to complete the game on "Give Me Deus Ex" without ever changing the difficulty.
 * The achievement description changes upon unlocking and/or after updating the game.