I'm surprised that emergent gameplay isn't more common amongst indie-AA titles. By Emergent Gameplay, I'm talking about what is seen in Syvalion, Clock Tower, and Westwood's Blade Runner.
Couldn't first figure out how a shooter would have similarities to point&click adventures but upon looking into it, looks like Syvalion mixes story elements as well as randomizes the stages.
Blade Runner is a classic and a must have companion if you love the movie.