Game Breaker / Deus Ex

Deus Ex

• The Laser Sight stands apart amongst all the other weapon mods. Attach this mod to your weapon and it basically eliminates inaccuracy, meaning the bullet will always hit directly in the centre of the crosshairs even when the target is so far away that the laser dot is practically invisible (and making further accuracy upgrades nigh-pointless). Given that the starting or Stealth pistols (both acquired in the first mission) can achieve one hit kill headshots even with no training, and given that you can find a Laser weapon mod in the opening mission (inside the bunker near the back entrance to the statue), attaching the laser sight takes all the guesswork out of aiming — which was one of the biggest challenges in combat in the original game. To note — this trick was so infamous that the Playstation 2 port, The Conspiracy, removes it altogether, and the only mod removed for the port. Certain gameplay mods (like Shifter and GMDX) remove the broken nature by making the laser account for your character's hand sway, meaning you could no longer assume the laser was in the centre of the crosshairs and had to be able to see the dot to be able to shoot accurately.
• The GEP Gun, to the point of being Complacent Gaming Syndrome. It's a weapon option offered to the player in the very first conversation in the game, and despite it being explained as a weapon whose only purpose is to destroy robots, its benefits are far more numerous. It's a semi-homing rocket launcher that is able to breach anything that can be broken in the game, up to and including locked doors and chests, negating the need to hack or lockpick open doors. Rockets are a relatively common find up until the endgame, and the only balancing factor is the large size of the weapon (2x4 inventory space, which will take up nearly a third of the player's inventory).
• The assault rifle was already a powerful weapon in its base form, and can be a death machine if it's upgraded at all. The player can start obtaining assault rifles in the very first mission (by killing the (only non-invincible) UNATCO trooper walking up the stairs right after you interrogate the NSF leader). The mods you get on the first two missions (which aren't difficult to find at all) make it a fearsome weapon. With the laser sight, it becomes perfectly accurate. Throw on a silencer, and you can mow through three or four mooks in a group before they know what hit them. Ammo becomes cheap and plentiful via enemy drops after the third mission, making it a go-to weapon for the majority of the game. Where it really shines is the alt-fire underbarrel grenade launcher - although the ammo is scarce, anyone who's hoarding it can effortlessly breeze past the mechs and groups of enemies in the final missions. And all this for just 4 squares of inventory space.
• Max out the Rifles skill and the shotgun loses the spread effect. All the power of a shotgun blast, all the range of a sniper rifle.
• The Dragon Tooth Sword is effective even with no skill points in melee - it's silent, it kills in one hit, it's easily obtainable rather early in the game, it can be used as an impromptu flashlight (since it naturally glows) rather than wasting bioelectric energy, and with some skill in melee weapons, you can break doors with it instead of having to look for a key. As a nod to this, The Conspiracy (the PS2 port) puts a Nerf on the damage by reducing it from 100 per hit to a measly 10.
• Simply getting one level of computers is enough to hack into any computer/security terminal without needing to look for the username and password. You won't have time once you're in to read all the lore emails, but a quick scan should add any passwords to your datavault and there's plenty of time to disable cameras (90% of the benefit of accessing security systems) if you're quick.
• The humble stealth pistol is perfectly accurate with Advanced pistol skill and a couple of accuracy mods, as well as being powerful enough to headshot-kill normal enemies with a single bullet and having the rapid-fire capacity to stunlock anything stronger with repeated headshots. It's also silent and perfect for stealth runs, where you'll have plenty of time to line up shots.
• The Speed Enhancement augmentation is incredibly flexible, boosting not only your run speed but also your jump height and distance (letting you take alternate routes and bypass platforming challenges), reducing fall damage (letting you skip one escape mission just by jumping off the roof of a three-story building) and letting you crouch-walk silently at high-speeds, making stealth much easier and making the silent movement augmentation completely redundant. And that's without learning to toggle it while bunny-hopping to rapidly traverse areas while using virtually no bio-electrical energy.
• The regeneration augmentation is also very powerful, basically turning any batteries or energy stations into free healing, counteracting drowning or radiation damage while swimming or navigating toxic areas (so it acts as a rebreather or hazard suit) and giving such fast health regeneration during battle that nothing short of a one-hit-kill can take you down. The high power drain initially limits its use, but that's easily rectified by upgrading the augmentation a few times and getting the power recirculator augment to reduce power costs across the board.
• Most of the augmentation canisters can be acquired in multiple missions to prevent any particular augmentation from being lost forever. There are two exceptions to this rule. The first is the augmentation canister next to the NSF commander in the Liberty Island mission, and the second is the augmentation canister in Versalife. The latter is the more important of the two here, thanks to both choices from the canister being freakishly overpowered, that being the Power Recirculator and Synthetic Heart. The first cuts augmentation power drain by up to 60% at max level, while the second increases the level of all equipped augmentations by one while active. Both are incredibly strong options- Power Recirculator can let you use multiple powerful augmentations at once with barely any energy cost, while itself only having a measly energy cost of 10 units per second. How about Aggressive Defense System, Speed Enhancement and Ballistic Shield on all at once? Or how about Cloak, Run Silent, and Radar Transparency? Alternatively, Synthetic Heart lets you use augmentations one step above what you should normally have access to, essentially eliminating the need to level up an augmentation all the way to level four. The energy drain is quite severe, but careful use of specific augmentations can make this a non-issue and the ability to spread upgrade points out to more augmentations adds lots of value. Ultimately, either augmentation is great for different builds.

Deus Ex: Invisible War

• The Spy Drone, a Biomod that can only be upgraded with Black Market Biomod Canister, can be maxed out long before leaving Seattle (by doing the Omar's sidequest in Club Vox and picking up another Black Market canister during a side mission) and can utterly trivialize most encounters. At max strength, it will knock out electronic and organic enemies, has a massive range and can be fired up to four times on one full energy bar before it needs to be recharged. (Compare this to the original game's Spy Drone, which took some time to find and upgrade completely, and required four upgrade canisters instead of three). As a result, certain maps become an absolute joke, as the player can sit in a room where a Repair Bot is present and fire the Spy Drone to their heart's content, while the Repair Bot will restore your energy ad infinitum.
• The Toxin Blade (a secret weapon found in the Minister of Culture's Apartment in one of the first areas you visit in Seattle) functionally makes one-on-one enemy encounters trivial, as it allows the player to Stun Lock an enemy, preventing them from attacking due to paralysis. You could rely on little else but this and stealth for the entire game and breeze through without much issue.
• The Electrostatic Discharge biomod applies an EMP effect to your melee attacks. Once fully upgraded you can disable a laser grid just by whacking the emitters with a baton or switch a combat robot to your side with a single strike.

Deus Ex: Human Revolution

• The Stun Gun offered on the very first mission only uses 2x3 of inventory space, requires no enhancements to fire effectively and ammo for it is found in abundance. Not only does it take down normal enemies in one shot, but it can also momentarily disable cameras and turrets. If you're carrying at least 25 shots before a mercenary boss fight, you can turn these encounters into a joke, trapping them in a permanent stun animation loop until they fall over.
• The 10mm Pistol's armor-piercing modification. On its own, the pistol is a reliable, accurate sidearm with fair range and one-shot takedowns for lightly-armoured enemies. With the upgrade, Heavies are two-shot kills. At the most. And it can be obtained very early in the game, in a location you can't possibly avoid going to, with a code that's very easily obtained.
• The tranquiliser rifle is naturally silent, doesn't require mods and lets you immediately non-lethally disable an enemy across the map with a single shot. The only downside is the long reload time but this isn't an issue if you pick off isolated targets.
• The Typhoon aug, when fully upgraded, makes mincemeat of the first three bosses. Use it, stun the boss, repeat. It is also an exceptional room-clearer, and ammo for it becomes a little more plentiful later on in the game. This is seemingly intentional however, as the game proper begins with the Typhoon aug prototype almost getting stolen.
• The Linebacker grenade launcher, which is a Pre-Order Bonus given at the end of the Tong's Rescue bonus mission during the return to Hengsha, can kill the third boss in seconds.
• Have the strength aug, hack augs and found a gatling turret standing around? Reprogram the turret and carry it around to get rid of any enemy since the thing has A) infinite ammo B) deals incredible damage C) is near unbreakable. If you are not seen carrying the thing, you even get the "Ghost" bonus.
• The Cloak augmentation was already powerful in the base game, providing seven seconds of invisibility per cell when fully upgraded as well as making you immune to cameras and laser grids. The Director's Cut version makes it even more powerful by allowing you to regenerate two energy cells rather than one, meaning you can use fourteen seconds of cloak for essentially free with a small cooldown, or combine the cloak with a double takedown and still have a few seconds of invisibility to return to cover without spending any nutrient bars.
• Since lockpicks and multitools no longer exist, hacking gets used for everything from opening doors to disabling laser grids and disabling traditional computerised security systems. It's also a major source of money and exp if you hack every panel and have a high tolerance for tedious minigames.

Deus Ex: Mankind Divided

• The Pre-Order Bonus "Micro Assembler" augmentation (found in the Tactical Pack DLC) makes several functions in the game insultingly easy. The aug converts duplicate weapons you find into crafting parts, which can be used to make weapon upgrades, augment ammunition, items - particularly Multitools (a digital Skeleton Key which can be used to hack any level door, security panel, or computer). Want to make more money than you know what to do with? Convert everything you can into multitools and sell them for profit. Sick of carrying duplicate weapons to a shopkeeper to sell for cash? This aug takes all the stress out of inventory management. The only downside is that it still costs Praxis Kits to unlock, and it can inadvertantly convert duplicate weapons (even unique ones) into crafting parts, but the downsides are menial compared to the benefits. Locked doors, safes, computers, and the money needed for Praxis Kits stop being a problem completely once you have this. It also has the benefit of opening up playstyles that are normally Awesome, but Impractical (requiring high usage of Biocell energy and/or Aug ammo), like a character who exclusively uses the Tesla or Blade Launcher to blaze through missions.
  • The Micro Assembler's usefulness even extends to the DLCs, where it can be brought in to both the System Rift and A Criminal Past expansions if the Tactical Pack is installed. Notably, the developers caught on to the broken nature of the aug and ended up giving it a Nerf in the latter DLC — it can't be unlocked until you find Guerrero in his cell halfway through the story.

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