SI:IG returns the Shmup genre to its roots and offers a satisfying expierience, hindered by a number bad design choices.
SI:IG tells a story – the story of the Shoot 'em up and the evolutionary changes that it underwent throughout the eras of gaming. The game starts out as little more than the original Space Invaders. However, shortly after downing a few invaders, the player is greeted with Charles Darwin's famous quote 'It is not the strongest of the species that survives, nor the most intelligent that survives. It is the one that is the most adaptable to change.' before being thrust into a somewhat more up-to-date version of the same game. From there onwards, the player begins a journey through each evolutionary step of the genre, as the game transitions between stages from a 2D vertically-scrolling Shoot 'em up to a fully-fledged 3D Shoot 'em up complete with variable, angled perspectives and modern sound effects. Fans of the genre are likely to appreciate the attention to detail in attempting to reflect each iteration of the Shoot 'em up, as early stages exhibit sound effects one would typically expect to hear in an old arcade game like Centipede or Asteroids, while later stages pit the player up against scores of 3D enemies who; rather than simply materializing in front of the player; fly onto the field from off-screen. As the player continues to progress, so too does the game's backgrounds continue to evolve. Scenery once consisting solely of white-to-black gradients or black and blue grids becomes replaced with single-colour backgrounds that pulse, breathe and vibrate in tune with the music. It is all very impressive to watch, and helps to emphasize just how far the cycle of evolution has gone.
Gameplay-wise SI:IG stays true to its core as a Shoot 'em up in its purest form. There are no special attacks, Bombs' or anything else that would otherwise be found in the Shoot 'em ups of this day and age, which comes across as slightly strange, considering that the central theme through the game is evolution. The player is able to unlock a total of ten different ships, each of which possesses remarkably different primary attacks. Perhaps it could be said that the ships themselves represent the evolution of the genre. After choosing a ship the player simply defeats wave after wave of enemies who appear on screen. This simplicity is partly what makes SI:IG so much fun to play. Make no mistake though, just as the player character and environments have evolved since their Space Invaders days, so have the opposition. Foes attack from all directions, front, back, the flanks and sometimes even from the middle of the screen, as they suddenly spawn right beside the player, which is unfortunately just one of SI:IG's many design flaws. On many occasions, enemies will spawn literally on top of the player with no prior warning, killing them in the process. Other times, a ring of opponents will spawn around the player before rapidly moving inwards for the kill. Unless one of the ships with omni-directional attack capability has been selected for the stage, the player will in all likelihood die within the next few seconds or so with no real means of escaping from that number of enemies.
This in turn brings to light one of SI:IG most prominent design issues – its enemies. The enemies have evolved. Fair enough. So has the player. Also fair enough. Only it seems that somewhere during cycle of evolution, the player characters either suffered a mutation of some sort, or they evolved to anticipate the wrong type environment. Half of the ships available for the player's use are incapable of dealing with the enemy's formations. Suppose the player chooses to use the ship from the original Space Invaders game, then a circle of enemies spawns in and surrounds the player. At this point, it is guaranteed that the player and the aforementioned enemies will collide, with fatal results. Some of the Bosses are also clearly oriented towards one ship or another. One such example includes a Boss that; within the opening seconds of the battle; surrounds itself with an impervious shield. Assuming that the player has opted to use a ship only capable of firing directly forward, they will be confronted with a problem - unless the player manages to close the distance between themselves and the Boss before the shield is fully erected, the player will be left with no means through which to destroy the Boss, and will be forced to simply wait for the time limit to expire. On the other hand, should the player choose to select a ship that does not need a direct path to be open between itself and the target in order to attack, the player can simply sit just outside the shield and whittle down the Boss' health without facing any resistance. These issues become more and more prevalent as the player progresses onwards through the game. Problems like this are only compounded by the fact that before starting a stage for the first time, the player has no idea what they are to be up against, and as such, it often becomes the case that the player will be left in either an impossible situation or one that is a lot harder to get out of than the developers had most likely intended. However once the player unlocks a certain ship capable of executing attacks in any direction within a specific radius,, the majority of these issues become redundant and are quickly replaced with another – the game simply becomes too easy. This lack of balance diminishes the overall gameplay experience and lets SI:IG down considerably.
Aside from 'Normal Mode' which presents the player with a series of stages to complete, SI:IG also features three other modes of play including the 'Music Mode', 'Bonus Mode' and 'Challenge Mode'. While the latter two offer an experience that is only marginally different to the main game; in that Challenge Mode generates a random series of ninety nine stages for the player to play while Bonus Mode simply includes extra stages that are unlocked as the player progresses through Normal Mode; Music Mode proves itself to be the source behind SI:IG's immense replay value. Using a music track of the player choosing, the said mode generates a level based upon the selected track, theoretically providing almost unlimited replayability. As long as the player has music on their hard drive, the Music Mode will have a level for the player to play.
SI:IG maintains a greyscale colour-palette that permeates every area of the game, including the menus. However, this is also tied into yet another one of the game fatal design flaws. Taking into account that the enemies, obstacles and player's ship are white, one would think that the developers would make the bullets a colour that would stand out against rest of in-game objects. However, such is not the case. Being white, the bullets have a tendency to blend in with the world around them, which can lead to deaths arising more from the player's inability to distinguish enemy projectiles from scenery. A particularly noteworthy example is found when dealing with a certain Boss, who literally occupies the screen in its entirety. The Boss is white. The bullets are white. Connect the dots.
SI:IG rides on its simplicity. In doing so, it manages to deliver an experience that; despite its countless design flaws; remains enjoyable for both Shoot 'em veterans and newcomers alike. All in all SI:IG is a title that is likely to appeal to dedicated Shoot 'em up fans and those who can abide by some measure of bad game design.