Games the shaped a generation: PC

3. Deus Ex
Ion Storm Austin | Eidos | 2000

The famously open-ended FPS/RPG hybrid set in a conspiracy-riddled near-future in which a man-made virus is ravaging humanity

What made it so great?
Options, options, options. Despite being swarming with terrorists, marines and robots out to kill you, it's possible to complete Deus Ex's enormously long campaign without killing a single person. It's equally possible to kill dozens of people without drawing a weapon, through hacking automated defense systems, luring them into traps and, on more than one occasion, simply uttering a word. More commonly you start out with a conventional mix of stealth and violence and quickly find yourself in a tight spot that requires some lateral thinking: "No ammo to take out these goons, but if I plant a proximity mine next to this laser-triggered alarm, I could trip it, then retreat to watch the fireworks..."

What's most entertaining about Deus Ex is when these schemes go disastrously awry: a guard walks past as you're placing the mine, you trip the lasers by accident before it's placed and soon you've reflexively tossed it at someone only to have it bounce back at your feet, and despite your heroic leap for safety the blast incinerates both your legs. Now you're half a man with no explosives, hardly any ammo and every guard in the building rushing towards your position. Got any other bright ideas? Actually, maybe those gas barrels over there...

Get ready to play
Definitely try the training course first. It teaches you some fairly advanced tactics like distraction, and culminates in an excellent freeform test of your abilities. There's even a way to particularly impress your employers at UNATCO by finding a secret room and getting a personal communique from Bob Page... a man you'll eventually meet again, under very different circumstances.

Been there, done that?
Deus Ex's famous co-creator Warren Spector later brought his magic touch to the class medieval stealth series Thief. Thief 3: Deadly Shadows is the dark delight that resulted: a sneaky epic that sees you wavering allegiance between three warring factions.