Dialogue
Some people judge video games based on their graphics, some on their replayability, but I tend to judge a game by its dialogue. It's the English major in me. I don't care if the graphics are breathtaking or if the game play is excellent, dialogue is the key element of the game for me. I think this is especially highlighted by what I've been playing recently.
Portal 2 has some of the best dialogue I've ever heard come out of a game. All of the characters come to life not only because of the excellent writing, but also due to the talent of the voice actors. GLaDOS's character development or Wheately's idiocy would not have been so compelling if the dialogue had been anything less than perfect. Most people complain that Portal is quoted too much, but I believe the attention that the game gets is entirely deserved. You cannot play through this game and not remember all of the insults that GLaDOS threw at you, or Wheatley proclaiming that brain damaged people are the heroes. I have never laughed so hard during a game without Player One around to bounce jokes off of. Nor, for that matter, have I ever become so quickly attached to the characters, and I attribute this to the outstanding quality of the dialogue.
Now, after I finished Portal 2, I decided to pick up Assassin's Creed, since I've heard a lot about the series from my brother. Unfortunately, while the plot is pretty interesting, I'm having difficulty getting through it due to the lackluster dialogue. While Desmond's segments show good writing, with interesting interactions between him and Lucy as you uncover the secrets of his past, Altair's portion of the game doesn't hold the same spark. His voice actor stands out like a sore thumb from the rest of the cast with his poor delivery of lines. Not only that, but the conversations that happened in the past are simply uninteresting. Unlike with Desmond, I don't really care what happens to Altair. In fact, despite how much I enjoy the game play (climbing things in video games has to be one of my favorite past times), I just can't get into the game. I would much rather play through my favorite segments of Portal 2 again than suffer through the boring cutscenes of Assassin's Creed (which is exactly what I have been doing.)
So essentially, what I'm trying to say is, a game will show the strength of its writing in the dialogue exchanged between the main characters. It doesn't matter how good the plot is, if your characters sound flat and uninteresting no one is going to care what happens to them. Similarly, poor voice acting will ruin an excellent script. It's finding the perfect combination of writing and voice acting that will lead you to the best story-oriented games, and those two things are key in any video game that I pursue (with several notable exceptions.)
Which, of course, begs your question "What about the silent protagonists, Rachel? What about games with little to no dialogue?" Well, dear reader, that sounds like a topic for Friday, doesn't it?