Enemies becomes friends, religions decay, and the universe you went into heaven to defend becomes unrecognizable.
One of the funny things about plots in video games is that the medium, in its current form, tends to lend itself to certain stories. Fantasy and science fiction aside, the average video game always has to incorporate obstacles, conflict, and struggle within the narrative. That's true of most stories, but in video games these elements are particularly palpable because generally, the player's function is interacting with those problems. Yet rarely do stories ever address the conflict itself, probably for the same reasons actors don't look directly into the camera. That's the means of connection with the video game world and to acknowledge it would be to break that bond. But the indie game Immortal Defense has managed to create a powerful story that marches right up to that element and forces the player to question everything about it. The end product is a tower defense game with one of the best stories I've ever experienced.
A tower defense game is centered around giving the player a variety of options for defending something, and then swarming them with enemies. From that perspective, the game is quite good. You set up nodes along a set path that enemy units travel upon. Each node has a variety of stats, you level them up with credits, and you get more credits by killing enemy units. There's enough variety in each node that players will be able to choose from a variety of strategies to beat each level. With a practiced eye you can tell which part of the path will slow ships down and lay a clever trap. Or, you can layer the ambushes in waves so that you don't get overwhelmed once the stronger forces arrive. Each campaign adds a layer of complexity to your strategies by throwing in multiple paths for enemy units, shifting terrain patterns, and a huge variety of enemies traveling in warp space. You can adjust the difficulty at any time, so there won't be many moments of getting stuck but plenty to occupy challenge junkies. Finally, the game manages to keep things interesting by having a boss battle at the end of each campaign that requires a totally different strategy each time. It's a unique take on the tower defense genre, and fans of it will find plenty to keep them busy here.
The story itself is that your character has been separated from his body and transformed into a path defender. You only exist in hyperspace and are able to intercept spaceships which are otherwise defenseless in this state. You leave behind your wife and unborn child for the sake of defending your home from invaders who are dead set on conquering your world. What makes the game so impressive is that it takes this scenario and flat out runs with it. The dilemma of returning to your body after you've achieved supernatural abilities. Your relationship with the mortals back on your home planet who begin to worship you as a God. And as the centuries drift by, the way history slowly gets re-written around you. Enemies becomes friends, religions decay, and the universe you went into heaven to defend becomes unrecognizable. The game handles all of these topics with deftness through a short round of dialogue before each mission. Characters often simply broadcast their prayers to you, the immortal defender, pleading for your help or asking for answers. The game even goes so far as to question your relentless destruction of life after you realize what you're doing is both wrong and meaningless.
John Thornton, the game's writer, explains in an interview, "The player can 'win' in a perfectly acceptable way by just ceasing to play in those final moments: he can set the game aside, never pick it up again, and that means that the player has come to his senses and abandoned his efforts. But that also means that the protagonist ceases to exist in any meaningful way. If the player finishes the game, it's a different kind of 'win.'
Special mention also goes to the soundtrack of the game, which was composed by one of the developer's dads. It's a haunting and evocative soundtrack that can be downloaded for free here. Several of the tunes have been stuck in my head for ages and these songs make the haunting solitude of your time in warp space all the more real for the player.
Kim Swift and Erik Wolpaw, the writers of Portal, noted in an interview that the key to putting a plot into a video game is by looking at the three variables of player, plot, and game as a delta. With the player as the basis, the game design and plot attach and come together at the top. All three forces have to be carefully managed and play tested throughout, so that the player is satisfied both with the game and how they interact with the story. Ideally, the game and story should intersect eventually in this figure. Here is a game that tempers all three variables responsibly: the player's input, the game's design, and the story's control over you. Immortal Defense, this game experience, is a fine thing, a new and wonderful thing. It pushes the boundaries of narrative in video games and it questions the very nature of the experience a game should provide. As the classy Helen Humes jazz song says when you turn on the game (lifted from the Public Domain, no less), "Where shall I go, when I go, where I go? Since you have sent me away. And what can I do, when I do, what I do?”