Those able to overcome GunValkyrie's steep learning curve will find an immensely satisfying game waiting to be enjoyed.
During the 19th century a meteorite that would later become known as Halley's Comet collides with Earth. Through extensive research conducted by Great Britain's leading scientists including one Dr. Hebbel, the British Empire soon finds itself wielding the power of Halley Technology at its fingertips, and with it, the power to conquer the world. Hailed as 'The Great Genius' by almost all of Britain, Hebbel overthrows Queen Victoria and seizes the throne for himself. As the Empire expands through numerous solar systems, further research into Halley Technology continues. However in 1906 Dr. Hebbel mysteriously disappears while conducting research on planet Valhalla. In the wake of his sudden disappearance, the Empire dispatches its elite military unit 'Team Dolphin' to Valhalla to locate Hebbel. Upon arrival however, it quickly becomes apparent that all is not as it seems, as the planet's colonists also seem to have vanished along with the Doctor, while the colonies themselves are overrun by giant insect-like creatures. Unfortunately that's about all you're going to get from GunValkyrie in terms of its story. Plot development occurs throughout the game in the form of text documents unlocked after the completion of each stage, with the occasional cut-scene cropping up for the plot's key events. Most of the game dialogue is spoken by the player's commanding officer Lt. Poe, whilst the player characters Kelly and Saburouta have a distinct lack of dialogue. In fact, Saburouta only possesses one line in the entire game.
Controlling either Kelly or Saburouta, players face off against the aforementioned creatures whilst continuing the search for Hebbel. Perhaps the biggest factor in contributing to GunValkyrie's steep learning curve is its unusual and downright awkward dual-stick control scheme. While the left stick controls forward and backward movement as well as rotation, it also controls all sidestepping movement. Clicking in the left stick and tilting it in a direction enables Kelly or Saburouta to use their boosters to evade incoming attacks or close the gap between an enemy and themselves with great speed when the situation calls for it. Unfortunately this set-up makes it very easy to accidently have Kelly do a cartwheel into a wall, when you intended to takeoff and fly over the wall instead. Even basic actions such as turning corners when running are made considerably more difficult due to the fact that the player characters slow to a walk before coming to a complete halt, when you let go of the left stick. This means that one essentially needs to wait for a split second for their character to completely stop moving before turning a corner, which can cause quite a few problems when pursuing (or being pursued by) fast-moving enemies. Although changing direction whilst on the move is possible, both characters have such a ridiculously wide turn circle that colliding with the environment is almost inevitable when on the ground. The right stick is used for adjusting the character's aim, although doing so feels very unwieldy due to the fact that only the upper portion of the player character's body actually moves while the lower portion remains facing in the last direction you were travelling in until it's adjusted using the left stick, thus essentially forcing the player to use both sticks to aim.
Fortunately most of the above becomes redundant after discovering (one way or another) the playstyle with which GunValkyrie is meant to be played. By using the left trigger to jump or boost straight upwards in conjunction with the left stick, it's possible to literally fly through many areas of each level, rarely ever touching the ground. Employing the use of this ability and shooting enemies whilst in flight is critical to success, as remaining airborne makes it significantly harder for enemies to land their attacks. Every kill earned while in the air contributes towards the player's Mobius Gauge which adds to the potency of the player's weapons as it increases. Upon filling the gauge to its maximum limit, the player character enters a 'Mobius State', affording them a period of invincibility in addition to a high-level of firepower. This gameplay style is great fun once one has had the time to get to grips with it. It becomes extremely satisfying to dodge incoming projectiles whilst performing somersaults and rolls in mid-air, all the while returning fire and cutting down wave after wave of insects.
GunValkyrie features an interesting graphical style that incorporates subtle elements of cel-shading along with the bog-standard, three-dimensional, realistic graphical style. While the character models are nicely detailed, some enemies look somewhat bland. Though the same could be said about the environments' textures, each level typically features some well-implemented lighting effects. One level that stands out for this reason in particular sees the player navigating an underground cavern, flying between islands suspended above pools of acid that give off a luminous green glow.
Though GunValkyrie's soundtrack isn't most atmospheric to date, it still has a few catchy tunes, one of which being the main menu theme, Valkyrie's Launch. While neither of the player characters are voiced particularly well, the lack of dialogue makes this only a minor issue. On the other hand Poe's voice actress did fairly well. Sounds accompanying the explosions are appropriate, but hardly anything to write home about. Weapons however have fared considerably better in the audio department and have a good degree of weight to them, in particular Kelly's Drive Gun, which sounds just as powerful as it looks.
Ultimately GunValkyrie is a 'love it or hate it' title. With clunky controls proving to be the largest obstacle to learning the game's mechanics, it's almost certain that many potential players will be put off from fully investing themselves in the game. Those who do persevere however and master the control system should find GunValkyrie to be a highly entertaining package that they will likely find themselves coming back to play over and over again.