This post is going to be about the antagonists and endings for a number of games. Consider this opening remark a big SPOILER ALERT for any game I mention in the text that follows. If you haven't completed a game that you see me begin discussing and you think you may want to play it in the future, you may want to stop reading at that point.
I began thinking about this issue upon completing Mass Effect 3 a few days ago. Like many who have finished it, I found the ending to be frustrating and unsatisfying. I thought about why the ending was so frustrating and about other games that had ended similarly and been similarly frustrating, as well as games that had ended differently and been satisfying. Ultimately what frustrated me most about the ending was what frustrated a lot of other people - that the game essentially invents a new protaganist in the final few minutes, completely changing the thrust of the entire three games worth of plot up until that point (though are are a small number of ambiguous hints earlier in the game).
Getting It Right
One of my favourite games is the original Metal Gear Solid. I've thought a lot about what makes that game so enjoyable, and one of the things that the game does is how effective it is at creating an antagonist that you're as interested in as the protagonist. It introduces you to the antagonist (Liquid Snake) very early on, and then proceeds to create a number of instances where the player character (Solid Snake) interacts with Liquid, either by confronting him directly, by overhearing his conversations, or by discussing his actions with other characters in the game. The game builds toward a fantastic couple of sequences between Solid and Liquid at the end that serve as both physical and philosophical battles between them.
I think the Solid/Liquid duel works on a number of levels, one of which is that as characters they create an interesting series of conflicts. That Liquid is every bit as memorable as Solid is a big part of this. But more than that, the main reason it works is because it provides players with a clear motivation. "Liquid is an intelligent but devious man and he must be stopped before he launches nuclear weapons" is compelling and coherent. The player is able to proceed through the game knowing what Solid ought to be doing and why (the why is very important), and when they finally defeat Liquid, there is a sense of release for having seen your task through to the finish.
Other games do this successfully as well. Final Fantasy VII, another of my favourite games, introduces you to primary antagonist Sephiroth roughly 10% of the way through the story and continues to highlight the struggle between him and your party right up until the final one-on-one battle between him and Cloud. When you beat Final Fantasy 7, you feel like you've reached the end of an important journey, having completed what you set out to complete.
Interestingly, the original Mass Effect does an excellent job of this too, and that's one of the primary reasons that it's my favourite game in the series from a narrative perspective. Even though the game does eventually reveal that the "real" threat is Sovereign and the other Reapers, it continues to use original antagonist Saren right up until the very end. The Reapers are set up as a larger foe for Shepard to continue to fight over the course of the next two games, but the first game is the self-contained story of the fight between Saren and the Normandy crew. When you defeat Saren, you have a sense of closure on what you've done in the game.
Getting It Wrong
The ending to Mass Effect 3 feels like a slap in the face, by comparison. You spend the entire second game learning about the Reapers, and you spend the entire third game preparing a team to fight them. I spent a little over 30 hours completing Mass Effect 3, and so I think I can fairly say that I spent 30 hours completing a variety of tasks under the impression that I was playing a game about ending a war with the Reapers. But then, with about 5 minutes left in the game, a super-intelligent AI which was controlling the other super-intelligent AIs shows up, and tells me that ending the war has nothing to do with any of the tasks I've completed up to that point, has nothing to do with the battles being raged across the galaxy that I've taken part in. Instead, it tells me that all I really need to do is make a philosophical decision about whether or not transhumanism is the direction that the species ought to evolve in.
Wait, what? Let me state this more plainly, in order to tie it in with my examples above: what the AI tells me is that I was never really fighting the Reapers to begin with. This is a violation of the trust that the game establishes between the player and the developer. It says that all of the time I've put into the game so far has been based on a false premise, a premise the developer knew was false. The issue isn't whether or not the ending is "happy" or "sad", but whether or not it treats the effort that the player has put into getting there as valuable. If the player is told that they're progressing toward a certain goal, and that goal is not only rendered unachievable but irrelevant, right at the very last moment, then the player can very easily feel like the time they've put in so far was a waste. The developer isn't just affecting the player's perception of the narrative, they're affecting the player's perception of the value of the real-world time that they put in to reaching that point.
I can think of another game that was heavily criticised when it was still new for doing something similar (though not at quite as late a stage of the game), and that game is Final Fantasy VIII. In FFVIII, the player is introduced to the sorceress Edea early on. They chase after Edea until they reach the end of the first disc (out of four, though the final disc has very little plot content on it), and then a large battle occurs in which the player loses to Edea and the primary protagonist, Squall, is seriously injured. The player then discovers, potentially dozens of hours into the game, that the real enemy is a sorceress from the future named Ultimecia who has been controlling the sorceress Edea. The player never sees or hears from Ultimecia until the very final series of battles at the end of the game.
Sound familiar? The similarities between the two games are striking. A super powerful force (an AI or a sorceress) appears to be your primary enemy. You then discover that the real enemy is another AI/sorceress, controlling the one you thought you were supposed to be fighting, who has a goal that is quite a bit different from the goal of the original AI/sorceress and who is defeated by very different means. Both games have been heavily criticised for the same reason - rather than being clever or compelling plot twists, the player feels like the rug has been pulled out from underneath them and their previous actions rendered largely irrelevant.
There's a distinction that I want to make clear here, because I think that it's important. I have no issue with characters lying to me within a game. In fact, I think Mass Effect 3 would have been a lot more interesting if it wasn't always so clear what all of the characters were thinking. What I do have a problem with is the developer lying to me, and that's what I discovered had been happenning at the end of Mass Effect 3.
I think the differences between the ways in which the first group of games (Metal Gear Solid, Final Fantasy VII, and Mass Effect 1) and the second group (Final Fantasy VIII and Mass Effect 3) treat their antagonists can be instructive when trying to decide how best to design narrative arcs and player motivations. Creating an antagonist (or antagonists) that the player can connect with and allowing the player to ultimately feel as though they've overcome the odds and defeated that antagonist will result in a much more satisfying conclusion to the player's experience. This is certainly true, at least, for games centred around action and adventure that deal with violent threats of a global (or larger) nature, though I acknowledge that it may not necessarily be true for more subdued games (like Heavy Rain).