Deus Ex

Note that the advice here is specifically for the original and unmodded singleplayer game, on version 1.112f.

Before playing

• Install Kentie's Deus Exe launcher; it has some great improvements for modern systems without changing gameplay.

• Deus Ex is a massive game that rewards exploration in many different ways. It's always worth searching areas thoroughly and talking to everyone you encounter for useful pickups, side quests and interesting story bits. Even then, every playthrough is likely to reveal something new.

• The first section of the game is what turns a lot of people off to it, but once you get past Liberty Island, things quickly get a lot better as the game opens up and you get a lot of cool augmentations. A good rule of thumb is to keep playing until you destroy the generator in the warehouse district to see if you're interested.

• Play through the tutorial. There are some obvious parts if you've played FPS games, but there's a reason it's strongly recommended before your first playthrough.

• The stealth section near the end of the tutorial may be frustrating to get through. Save before attempting it the first time, then try a few times. If you just want to move on, reload the save and do the following: Go straight downstairs and look for the thermoptic camo on a crate. Go back upstairs and reset the test by pressing the button. Use the thermoptic camo when coming back downstairs (note that "Equip" only puts it in your hands, you have to "use" it to make it work, confirmed by seeing the icon on the right side underneath your augmentations), and avoid bumping into the soldiers while running towards the exit.

• On unmodded installs, the only thing that the difficulty level changes is the damage you take from bullets. Everything else (credits, ammo pickups, dialogue, damage from other sources, enemy AI/behaviour, et cetera) is the same.

• On Hard and Realistic, early on, you can be instakilled with a single shot from a sniper rifle if it hits your head or torso. On Realistic, a single pistol round can do the same.

• You can upgrade your skills anytime in-game. In most cases, it's better to wait until you feel that you need a skill instead of upgrading it prematurely. You don't need to spend any skill points in the character creation screen; they'll be available after you start the game.

• Your appearance has no effect on gameplay, and your name is entirely cosmetic.

General gameplay and starting out

• When Paul offers you a choice of weapon at the beginning, it's recommended to take the GEP Gun, as you won't get another GEP gun for a long time and the other two weapons can be found elsewhere in the level (a good chunk of enemies have the minicrossbow, including some dead bodies near UNATCO, and one enemy has a sniper rifle). It's useful even outside of combat, as it can easily bust through breakable doors.

• Upgrading the Computer skill to at least Trained will allow you to hack any and all computer terminals. While it's useful for disabling cameras and the like, it's also extremely useful if you want to explore and read everybody's emails to learn some interesting tidbits. Upgrading beyond that is generally to give yourself more time to read things.

• Deus Ex doesn't really tolerate the run-and-gun approach early on; try to be more methodical when starting out. Use your Riot Prod on individuals and sneak around groups of enemies.

• If the aiming reticle is shrinking too slowly for your liking and you're getting frustrated, bumping Pistol skills up to Advanced is a valid option. The pistol is useful throughout the game (as is the minicrossbow, which also benefits from Pistol skills), so you don't have to worry about "wasting" skill points early on.

• If you free Gunther and he accidentally locks you in the room where he was kept prisoner, check to the left of the door. There should be a brick that you can use to open it and avoid a softlock.

• At the top of the Statue of Liberty, be sure to search the room. There is an augmentation canister here, and it's the only one in the game that gives you options for your arms.

Weapons

• When going for close-range non-lethal takedowns with the Baton or the Riot Prod, never aim for the head, as it'll reduce the damage done.

• If an enemy is stunned or covering their eyes (from pepper spray, gas grenades, or other reasons), they take quadruple damage.

• Attacking an enemy point blank from behind gives a massive 10x damage boost.

• Weapon range modifiers don't work as one would expect on projectile weapons due to a bug. Only hitscan weapons benefit from them.

• If you equip a laser modification to a weapon, remember to turn it on when you equip the weapon, as it doesn't do that automatically.

• Some weapons have incorrect information in the inventory screen. Most notable are the plasma rifle and the PS20, which have damage equal to that of the stealth pistol, but with a far lower rate of fire. They should probably be avoided.

Skills

• Avoid upgrading the Swimming and Environmental Training skills early in the game.

• Lockpick/multitool skills give 10%/25%/40%/75% bypass per item.

Augmentations

• Some augmentations are considered near-useless, some are pretty good, and a select few are extremely overpowered. Since each canister has a choice between two different augmentations, it may be difficult to choose between them. Note that a book found near the beginning of the game contains a list of these augmentations, so this list isn't really a spoiler. The spoiler section under "Choosing" gives "future usefulness" information so you don't have to guess if an augmentation will be a lot more useful after a certain point.

• Note that most augmentation choices have more than one canister. If you miss one, it's possible to find another one with the same contents in the future. There are two exceptions, but they are both very visible and hard to miss. The first is the arms augmentation at the top of the Statue of Liberty and the second is surrounded by several other augmentations and an upgrade canister that you will almost definitely pass through.

• Arms: Combat Strength or Microfibral Muscle. How to choose: Microfibral Muscle lets you be pretty creative with solutions by shuffling items around, such as stacking crates to climb to areas. Combat Strength pairs well with a weapon you obtain in the mid-game.
• Legs: Speed Enhancement or Run Silent. Speed Enhancement can also affect your speed while crouching.
• Subdermal (1): EMP Shield or Ballistic Protection. Note that EMP shield only reduces lost bioelectric energy and NOT damage from electricity. How to choose: The proportion of enemies/situations in the rest of the game that will allow you to make use of either choice is roughly the same as up to the point you found the canister.
• Subdermal (2): Cloak or Radar Transparency. Both use the same (massive) amount of energy. How to choose: The proportion of enemies affected by either is roughly the same as up to the point where you find the canister (with a few large bots thrown in occasionally), so choose the counter to whichever enemies are more annoying for you.
• Torso (1): Aqualung or Environmental Resistance. How to choose: Both are very situational and have an equivalent item with similar effects, so it's mostly a choice between exploration and damage reduction if you choose to install.
• Torso (2): Regeneration or Energy Resistance. Energy Resistance also covers explosion damage. How to choose: The proportion of enemies that deal damage covered by Energy Shield is roughly the same (maybe slightly more) in the rest of the game as up to the point you find the canister.
• Torso (3): Synthetic Heart or Power Recirculator. Synthetic Heart only has one level. Augmentations don't have a "level 5" that gives you more advantages when an augmentation is maxed and the heart is activated. How to choose: There aren't enough upgrade canisters in the game to max out all of your augmentations, so if you're aiming for having everything activated at once, that's something to keep in mind.
• Cranium: Aggressive Defense System or Spy Drone. How to choose: The proportion of enemies that have weapons affected by the defense system is a bit more than up to the point that the canister is found. It also requires some upgrade canisters, as otherwise, things may detonate a bit too close to you.
• Optics: Targeting or Vision Enhancement. How to choose: Vision Enhancement can make it easier to see enemies in the distance in an open space, or, if upgraded, around corners and in other rooms. There are a few places where that can come in handy. Targeting helps to increase damage and accuracy, which can help with certain weapons if your skill with those weapons is low or you're damaged.

• Generally speaking, the best augmentations in the game are considered to be Regeneration, generally considered to be overpowered, even if left at level 1, and the power recirculator, reducing bioelectricity usage by a large fraction. The worst is generally considered to be the EMP Shield since it's far too niche to be of much use.