Despite minor imperfections, Killzone: Liberation sports a great presentation coupled with outstanding gameplay.
Except that it's not strictly speaking Nazis you will be fighting in Killzone: Liberation. It's the Helghast, those murderous, unfortunately-named Cenobite look-alikes (I mean, seriously, how could a race of genetic degenerates named Helghast be anything other than freakishly evil?) And they do make a formidable foe: after the events of PS2's original Killzone, the Helghast are running roughshod over Southern Vekta, revelling in their Wehrmacht-inspired aesthetic, shooting down civilian transports, torturing helpless damsels in distress, and continuously calling you "Vektan dog." This kind of aggression simply will not stand, so the players, as the Vektan soldier Jan Templar, take the fight to the enemy by, essentially, blowing up the ever-loving crap out of every single Helghast obstacle they find standing in their way.
In reality, as corny the above may sound, it makes for a much, much more compelling setting than any other World War II - inspired shooter on the PSP. The ethos and the aesthetic of the game are self-consistent, and they provide the backdrop for one of the most intelligent, challenging shooters to grace the PSP. Liberation's best-kept secret is that despite its seemingly superfluous story and comically over-the-top delivery, it is as solid as shooters get on the PSP or any other console. The seeminly run-and-gun nature of Liberation actually disguises a very clever environment-based combat mechanic, where not making clever use of cover is tantamount to suicide. This mechanic is further boosted by the alarming intelligence of the enemies, who will work in squads, lay down covering fire, flush you out of cover with explosives, and generally make your life miserable (about the only thing the Helghast haven't quite mastered, apparently, is dodging grenades -- though they tend to be very good at announcing their presence.) Those expecting to breeze through Killzone: Liberation's 15 missions will be frequently treated to the loading screen, but the game's designers stopped just shy of making the game unbearably frustrating, instead turning it into a fiendishly challenging yet ultimately rewarding exercise.
The game's tactical roots are evident from the very beginning. No longer is the player able to carry a wide assortment of weapons, explosives, and medkits throughout the game. It's all handled in a decidedly Resident Evil-esque fashion, with health packs, grenades, and weapons being gathered from stationary supply chests. The broad range of weapons presented to the player is equally well thought-out, with each weapon being suited towards a particular situation. As players will face a variety of tactical situations throughout Liberation, the arsenal at their disposal will likewise have to be customized to best fit the situation. Each weapon serves a unique purpose, with assault rifles being the preferred tool for mid-range combat, shotguns and machine pistols being used for CQB, and sniper rifles being utilized in those circumstances where long-range combat is preferred. All of these have their place in the game, and all see almost equal amount of play-time.
From a technical standpoint, the controls in the game are about as tight and responsive as they could be. Players will control Templar's movement with the PSP's analog stick, while the face buttons are used to fire the primary weapon, or to chuck the variety of explosives and grenades at their disposal. The auto-aiming feature is implemented nicely, with automatic level adjustment and indicators for grenade placement thrown into the mix. Targeting may occasionally get frustrating as shots tend to go astray when using an automatic weapon, but with plentiful ammunition being strewn about, this is hardly an issue.
Visually and audio-wise, Killzone: Liberation is not spectacular, but it isn't exactly bad, either. The worst criticism one can subject the game's visuals to is that they definitely take a backseat to gameplay and serve to underscore it rather than wrestle with it. The characters appear rather small on the screen, and the levels, while functional and well-designed, are a far cry from impressive in their general appearance. This very aspect of level design, however, factors exceptionally well into the game's flow and continuity, providing the player with a battlefield that is less stunning but much more functional than most.
The level design similarly turns out to be a fantastic asset during co-operative multiplayer games, which are really much more fun than they reasonably should have been. While the competitive multiplayer matches tend to be either too chaotic or non-existent (Liberation does not support infrastructure mode gameplay, relying instead on the very limited ad hoc mode), playing through the game's co-op missions with a buddy puts a whole new spin on the game. Tandem tactics come into play as flanking maneuvers, covering fire, and leapfrog advances suddenly make sense and are utilized in a meaningful, practical fashion. It's a shame, then, that Liberation's suite of multiplayer options is so limited, relying on connecting to the buggy killzone.com website to unlock extras for single and multiplayer games.
Killzone: Liberation is far from perfect. Many gamers will sneer at the lone-wolf premise, the ham-fisted aesthetic, and the bogged down multiplayer. The single-player campaign, while challenging, ultimately ends up being short, and there is little in the way of extras to unlock once the game has been beaten. These gripes notwithstanding, the content that is present in the game is ludicrously good and addictive in its simplicity and polish. Killzone: Liberation may not have the compelling story or visual presentation of its big-league competitors on the modern consoles, but it will more than satisfy the shooter jones for those who still want to put Nazis through their paces but are sick of the hackneyed World War II theme.