I played Killzone 3 over the span of 2 days. This isn't because the game is short, but it's because I was gripped from start to finish and a human bodily function known as sleep stopped me from finishing it in the first day I bought it.
Not many games grip me the way Killzone 3 did. For starters I'm nototriously stubborn when it comes to ANY sci-fi script. Not a huge fan of the genre mostly because it can get so convoluted and immediately makes me uninterested. This goes for films as well as games.
Killzone 3 starts off in the Helghan facility prison. You go through what is a point-to-point tutorial, similar to other games. Ending with protangist "Sev" pointing a gun at "Stahl".
The game goes through a fairly simple narrative, there are two characters in on the Helghast side which are deemed important: Orlock and Stahl. They're essentially tearing apart the government and people of Helghan. Orlock is the genuine ruler, but Stahl wants more. He developed the weapons and technology to let the Helghast get where they are. Orlock actually gives some passion and motive to the "people" of Helghan, they're evil, but have purpose.
Meanwhile the ISA consists of 3 important characters and essentially one squad. I won't spoil anything that happens on the ISA side because it gripped me and intrerested me most, and there are certain plotpoints that are very interesting towards the war going on.
This is the thing I enjoyed most about Killzone 3. It feels like war. I've played my share of Sci-Fi FPS games taking place in a war, and NONE feel as genuine as Killzone 3's. It feels like this COULD take place. The general art style shows war-torn areas of Helghan and as the ISA we make it even more war-torn.
Weapons feel brilliantly powerful, unique, and you are treated by ARMORED opponents. Headshots will take them down usually, but body shots you can empty an entire clip before you take down your VERY formidable opponents -- the AI, very clever.
Let me give you a short gameplay story of HOW clever : I was stuck at one point in the game where I kept repeatedly dying, because I was being a bit sh*t. There was this one helghan BEHIND me at the point the game autosaved me where I was dying : every time I died, this clever AI did something different. It wasn't following a script. It was reacting to where I went and to what I did. If I got close he could take me down very quickly with a few shots, he would also hide on occasion, and in circumstances where I ignored him and tried to get behind cover he would throw a grenade and move closer to me. NO other game, and I mean NO other, felt this unique per-scenario. What Guerilla have essentially done with their AI is what Valve did on Left 4 Dead -- every single circumstance feels unique.
Talking about the campaign overall, with no spoilers, you get to do a LOT. You explore a vast area of Helghan, and some of those areas are extrmeely unique. There are also moments where you pilot, or are shooting in a piloted vehicle, and these moments are incredibly fun (a moment where you're in a mech and mowing down the helghan just is a bit TOO satisfying).
Graphically and artistically, it's amazing. Guerilla, I feel, have the BEST artists in this industry, and the tech to go along with that. Lighting is stunning, there is a LOT going on the screen at once, and the game never stutters. It's a huge, really HUGE improvement over Killzone 2. The level variety and backdrops are beyond stunning. I found myself just absorbing every inch of every environment because there is something going on every SECOND of that 360 degree world (there are points where you should probably be looking forward, but Guerilla have bothered to add stuff to the sky). It's because of this I feel Helghan, this future, basically everything -- COULD be real. Every other sci-fi thing, including films, never really gives me this feeling.
Sound design is the best. Seriously, the BEST. The element of this feeling like a war is largely down to the graphics but a huge portion of it is down to the sound. Everything has a mechanical sound, the guns sound BRUTAL, the voice acting is magnificent especially on the Helghan side (Malcolm McDowell and Ray Winstone give truly believable performances) and this is all topped off with a great sci-fi score that perfectly reflects the mood.
I haven't yet played multiplayer. I did play the beta and enjoyed it but I think that Killzone's single player is epic enough to recommend to everyone who is looking for a dark, realistic sci-fi world.
Overall, I whole-heartedly recommend everyone to play this game, and I really hope everyone who does get it finishes the game, they will know what I'm talking about with this review. Oh, and without spoiling -- Killzone 4 COULD be twice as good.