Allow me to make one thing clear from the very beginning: The heart and soul of this game lies in the Co-Op, and the marketing for it has always made that point very clear.
Now that this is out of the way, let's be tidy and start with the Single Player aspect of the game.
As far as length goes, a skilled gamer with a minimal preference to explore will complete this game in 7 to 9 hours under Normal difficulty (three settings: Easy, Normal, Hard). The bulk of the game is challenging, if not too hard, and so are the boss fights (Yeah, you heard it right, old-school bosses in a shooter. I loved that) so long as you realize that you cannot just fight them blindly: They require specific strategies to take down, much like ye olde bosses from ye olden games. Which is a huge plus in my book. Bosses grant character upgrades, but unlike in co-op, they are rather limited. More on this later.
The storytelling (notice storyTELLING specifically), as in how the MAIN plot is presented to you during actual gameplay, is pretty utilitarian. Nothing to write home about; Won't bore you to tears but it's not much better than a simple "meh". It'll simply suffice to give you a reason to go around. The voice actors are actually really good at their job. EUROCORP CEO Jack Denham is particularily amazing, there is something about his voice and performance that simply drills right into your soul.
Now, the thing with this game is that there is SO, SO MUCH STORY underneath the TELLING. What is presented to you is nothing but a veil of lies and deception: There are much deeper reasons, much deeper CAUSES behind the CONSEQUENCES that you get to experience during actual gameplay. If you like exploring, a series of collectables in the form of hidden propaganda, business cards and intelligence are spread throughout the delightful scenarios. After you have collected those, you can read deeper into the story in a menu called "InfoBank" accessible by hitting the 'tab' key mid-game. The more you collect, the more you will know, and once you have enough, if you like conspiracies and connecting the dots, you will see through the lies and discover the unlikely puppet master behind the entirety of the plot, choreographing everything to play right into his/her agenda. I will tell you this much, nothing in the game is an accident. And even though I cannot say I particularily endorse having to go out of your way to discover what the story REALLY was about, if you do, you will be rewarded with a rich understanding of a world that is significantly deeper than what you see on the surface.
Ultimately, the Single Player campaign's story is what you make out of it: Collect everything and read into the backstory and it is very interesting to see how it all lead to what you actually get to play. Don't, and it SEEMS like an empty, average and meh generic shooter full of plot holes.
Now, let's go into actual gameplay: Fast and frantic. Both you and your enemies have higher health pools and resilience than what is seen in other games like, say, Call of Duty. Also, weapons have very tight accuracy and spread even when firing from the hip: This is very reminiscent of glorious PC shooters such as quake, and even though your movement speed is lower, strafing and jumping will not affect your hip firing accuracy. Shooting missiles or explosive shotgun shells at enemies' feet is particularily endearing, and a delicious throwback to using rocket launchers in Unreal Tournament. The ultimate feel of the game is a very fun and genuinely refreshing and enjoyable mixture of old-school arcade and modern FPS gunplay.
Then there is your DART6 chip: Gives you the ability to highlight enemies in orange against dark backdrops and see them through walls as well as take more bullets, deal higher damage and slow down time (this last thing only happens in Single Player). This skill, the DART6 Overlay, lasts for a short while and recharges through time as well as murdering enemies. Beside this, there are DART6 Applications: Unique skills that can be directly and offensively aimed at enemies and are only recharged through combat: Killing sprees, multi-kills, headshots and optimal usage of Applications all grant bonus points towards recharging your other Apps and the Overlay, as well as giving you a rating at the end of each stage (how very delightfully old school this is, actively rewarding balls-out skill).
Examples of apps are Breach, which can disable enemy armors and shields, Suicide, which causes an enemy to commit suicide with a grenade, taking out any surrounding foes, Backfire, which causes up to three enemies to have their weapons backfire and cause damage to themselves as well as making them more vulnerable, Persuade (based on the original Syndicate's Persuadertron) which has an enemy change sides for a while and ultimately blow his own brains off...
Enter Co-Op, where pretty much everything I have said regarding gameplay gets MUCH BETTER.
Let's start with Applications: There are more, they can be customized, they can be upgraded. There are SEVERAL of these, none of them senseless fluff or filler. Things like putting up a shield for the whole team which, once depleted, results in an EMP blast that incapacitates nearby enemies, Damage Link which enhances the damage output of all team members momentarily, Squad Heal (exactly what it says on the tin) and so on. All of them are recharged in the same way as their SinglePlayer brethren: Through skillful gameplay.
The Breach Application, available always and by default, can also be applied to friendlies in co-op, healing or reviving them and granting bonus points to the healing samaritan. This in turn encourages tight team play, as aiding your teammates directly results in benefits for you. While breaching (healing or reviving) a teammate, you can move around and defend yourself, although strafing and jumping around while holding down 'E', while not impossible or even particularily hard, proves an entertaining task.
By earning Experience (basically the points you get by generally being awesome) you level up your character, getting a series of permanent upgrades
And this one of the aspects which is just monumentally better in co-op: As you level up, your character transforms into a lithe, high-health murder machine, reminiscent of Quake, Unreal, Serious Sam and the like. Upgrades such as 30% higher health, 20% better armor, 50% better accuracy and spread and infinite sprint are all geared towards making your character more and more like ye ole' FPS protagonist that jumps around dodging bullets and launching rockets. Upgrades are permanent and, by level 30 (takes a good while) you'll have them all.
And you will need them. Them, and teamwork. Because Co-Op is nothing like Single Player. It will kick your ass. Available settings: Normal, Hard and Extreme. Easy? Pshaw! Easy is for little girlymen!
Once you get closer and closer to level 30, you'll become increasingly "one-man-army"er, and if you are skilled in shooters, it's likely that you'll be able to beat all co-op missions in normal by yourself. However, Hard and Extreme will DEFINITELY require you to sweat bullets and have equally skilled, max-leveled peers by your side if you do not wish to be sodomized by the game. You will need good aim, a penchant for moving around dodging enemy fire like crazy and, at the same time, a blood-written oath to stick together and apply TACTICS. Yes, you heard me, TACTICS. Such as MMORPG favorites by the likes of slowly luring enemies away from their pack. Healing, reviving and team-orientented DART6 Apps will be the order of the day. Oh, and bullets flying everywhere.
The missions are slightly randomized, more so as you ramp up the difficulty: Different types of enemies will randomly spawn or come in dropships in different parts of the stages completely unpredictably. And even though the "main forces" will always appear in the same place, as difficulty increases so will the number of random enemy spawns. This, and the fact that enemies use wildly different strategies in harder difficulty settings instead of blindly charging you and spraying lead will ensure every play through every stage will be different and just as exhilarating as the last.
Recommended for people who like reading into backstory (such as MGS fans), frantic old-school gunplay and tactics(IE people who enjoyed 1990's PC FPS) and co-operative multiplayer.
No, there is no PvP competitive multiplayer.
