You will soon have your God, and you will make it with your own hands.
It seems to be common knowledge that the PS2 doesn't have an FPS that's worth playing. X-Box has Halo. Gamecube has Metroid.
And the PS2 has Deus Ex.
The early impressions aren't good. The graphics are bland. The plot cliched. ("Oh, I'm a cybernetic supercop who wears his sunglasses at night? How quaint.")
However (after playing through the dull, optional but necessary tutorial) you soon realise that you're free to do what you want within your mission.
It's not just weapon choices but strategic approaches. There isn't a right way to do any mission. You can be Rambo and try to shoot your way through. Or sneak around like Snake and avoid/disable guards. Or hack into their security systems and get their automated defences to attack them. You can change your tactics as the situation demands it.
While the game looks like your typical shooter it plays more like a first person roleplaying game. Skills do come into play, however points are awarded not by killing all and sundry but by completing mission objectives, finding secret areas and sometimes finding a subtle solution to a problem.
Even simple problems have multiple solutions. The common problem of a locked door can be sorted by finding the right key. Or using a lockpick. Or by hacking into a nearby security system and unlocking it electronically. Or, if you don't care how much attention you'll attract blowing up the door using an explosive.
Customising your agent also offers you choices that affect how you play the game. Do you augment your agent to run fast or run silent? Resist bullets or energy weapons. You can even give him a portable floating camera if you want.
People within the game aren't just lifeless drones either. They react not only to what you say but what you do. Pull out your gun in a crowded place and they'll run. Hell, you'll even get told off by the boss for looking into the ladies room back at base.
As a result, every choice feels like it actively affects the game. Every conversation branch feels like it's going to affect the situation. Simple decisions made early on feel like they have a real impact later. This also means that two different players might have completely different experiences playing the game.
There are some differences to the PS2 version. The character models have been improved. Some of the hub models have been changed. The loading times are longer. And the control system has been tweaked. (The inventory system is much better than the PC version.)
It's the choices offered and the way the game adapts to them that makes this game special. You really feel like your choices and actions make a difference. If you want an FPS with depth seek this out now.