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Take the obligatory plot. You are some average Joe named Daniel Garner who ends up in purgatory after you and your wife die in a car crash. For all you non-Catholics, purgatory is a place people are sent to atone for sins and Daniel's atonement takes the form of killing demons for the big man himself. His last bit of atonement involves killing four of Lucifer's generals. He is promised that after killing these four he will be reunited with his wife in Heaven.
While Daniel is eager to see his wife he gets a hot sidekick in purgatory, Eve. Yes, that Eve. The whole bit the apple and started the whole sin thing. Turns out purgatory is a hot place as Eve goes topless, only maintaining a small bit of modesty with some rigidly placed hair. It’s the kind of mindless boob display that pervades video gamers and reinforces the opinion that video games are nothing more than immature, adolescent male fantasies.
Plus there's the fact that according to the Judeo Christian tradition when Eve bites the apple she realizes she's nude and is ashamed. So now she just suddenly decides to go all quasi-nudist in purgatory. And where is Adam? And why is she in Purgatory? Silly me, I'm trying to apply knowledge and reasoning to a video game. How stupid.
Moving past the asinine plot let's get to what this game is really all about: shooting up demons. What separates Painkiller from the ocean of FPS is the unique weapon designs. Take the titular painkiller, a weapon that serves as both a close ranged set of rotating blades and a medium ranged laser that burns anything that gets between it and its target. You can also shoot out the rotating blades to a moderate distance, creating a weapon that is both visually and functionally unique.
Even the most mundane weapons have an extra dimension. The shotgun's secondary fire is an icy blast, allowing you to freeze stronger enemies that then can be taken down with a single blast. And your standard rocket launcher is also a gattling gun. The interesting duality of all the weapons creates for more nuanced gameplay given the fact that you are pretty much shooting swarms of mindless enemies the entire game.
Yet every level has its own unique set of mindless enemies. The attacks and behaviors of each enemy are slightly different from the rest of the enemies. Some will charge directly while others will keep their distance as they fire from afar. More importantly, most enemies have different weaknesses. Some are best taken down with a freeze/shotgun blast combo, others are best staked from afar with the awesome stake rifle. This isn't like Doom where you can conceivably beat the game just using the shotgun. Throughout the game you'll be frantically swapping and snagging specific weapons and ammo.
The core problem is that the action set-pieces take place in either too big or too small a place. In the smaller areas you find either it's too easy to take down bottlenecking enemies or you are going to take a brutal beating no matter how agile you are. In the lager areas it's often unclear where to go next after you've defeated your enemies. The game attempts to solve this by using the compass system, which has a tendency to work only when you don't need it. This creates numerous instances where you'll spend minutes exploring every nook and cranny to find the next checkpoint or hunt down that last enemy. In this style of shooter pacing is key. If the level isn't constantly pulling you into one direction it has not been designed properly.
However, I will say I found the settings of the levels distinct throughout and never felt like the game was recycling settings or set-pieces, unlike a certain popular shooter series (yes, Halo, I'm looking at you). While I highly doubt that there are Vienna style docks or Victorian opera houses in purgatory they make memorable backdrops for the frantic action of Painkiller.
The game has a couple of design hooks that, while interesting, are poorly designed. The first is the soul system. Every demon you kill drops a soul and picking up that soul will replenish one point of health. Problem is that after killing a demon it takes several seconds for the soul to appear. In the middle of frantic action where you are constantly on the move, waiting for a soul is a nuisance.
Then why bother if it only of marginal benefit? This question is even more relevant when you consider that you health is replenished at every checkpoint. The answer is because after collecting 66 souls you transform into demon mode. Once in demon mode time slows to a craw and you can freely blast away your opponents. I ran into many scenarios where I was one soul away from 66 and saved it for the next wave. Having to wait three seconds for the first soul to appear is a mini-eternity when the action is so frantic and intense.
The other big hook is the card system. Each level has a card you are rewarded for completing a specific task in the level. These cards are essentially buffs that make the game easier. Some increase your health, damage and speed while others have specific effects on the environment such as the ability slowdown time. Silver cards are constantly in effect whereas gold cards are activated for a brief period. The cards are more like quasi-cheat codes that make the game marginally easier. You can conceivably beat the game without them, but they make some of the later levels much easier to handle. Since it isn't essential and there are only a handful of things the cards change it's a lost opportunity to add another full layer of depth to the gameplay.
As much as I've run Painkiller through criticism purgatory it's still an enjoyable experience. The insane action and crazy weapons made for an addictive and enjoyable shooter. But for every five minutes of enjoyment there was one of frustration at poor game design. In this style of shooter every moment not spent shooting is one that should be building up to the next fight, not spent waiting or searching.
For the shooter fan it's a no brainer, the action and intensity will hook you right in. For those less in tune with the genre the numerous flaws make for a frustrating experience. If you're a FPS junkie and have played all the greats, Painkiller is your fix. For everyone else you're probably better off trying out any number of the great shooters you haven't got around to playing yet.