So I played back through the "No Mercy" campaign of L4D last night, with the Developer Commentary option on. This is pretty much the same deal as the developer commentary thing in Portal. As you go through the levels, there are 3D speech bubbles hanging in mid-air in various places. You look at them and hit X, and the game plays an audio clip with one of the devs explaining something about the game design. Sadly, the clips aren't as interesting in L4D as they are in Portal. Too many of them seem to be about the music system, for instance. And Gabe Newell's ego-trip opening commentary is downright eye-roll worthy.
Besides the commentaries themselves, one other interesting thing about commentary mode is that special infected don't spawn the way they normally do, and regular infected pretty much ignore the player. This may make the game more fun or less fun, depending on how good you are. But one thing for sure: as the human player, you'll almost never get damaged. In fact, I think I took 0 damage in three out of the four levels in the No Mercy campaign. This is a big contrast with normal mode. Because the bots never take the initiative, as the human player you end up being the point man on the team pretty much all the time. Which means you end up bearing the brunt of most attacks, and take the most damage. So normally, the other players are the ones healing you. But in commentary mode, where the zombies don't attack the human player, it's the other way around: you end up healing the bots.
I still haven't played L4D enough to master all the controls. And because I rarely heal other people, I'm particularly clumsy with the healing controls. I always confuse right trigger (heal yourself) with left trigger (heal teammate). Which leads to the story... Myself (I usually play Louis) and the other three had just gotten into the safe room on the ground floor of Mercy Hopsital. Both Bill and Zoey were a little more dinged up than I like, so I took my medkit and healed Bill. Actually, I screwed up and started healing myself (RT) but stopped real quick and healed Bill (LT) instead. Then I picked up another med kid, and ran over to Zoey. I start tapping LT to heal Zoey. And this is where the hilarity starts. I didn't realizing that when I healed Bill, I used up my medkit. And so the game automatically switched me back to my shotgun. And the game didn't re-switch me back to medkit when I picked up the new medkit, either. So instead of holding a medkit, I'm holding my gun, and left trigger does my melee attack. I'm tapping LT in an attempt to heal Zoey, but instead I'm smacking her right in the face with the butt of my shotgun! And it takes me two or three taps of LT to notice, so I've hit her two or three times before I notice! Man, you wanna talk about instant red-cheeked embarrassment...
So I switch to the medkit and begin actually healing her. But then the evil little nagging voice in my head is all: "Oh sure, first you beat her up, but THEN you heal her so nobody can tell you've been hitting a girl!" The domestic violence overtones are just too thick at this point, and I can't help but start snickering at my own twisted imagination. I can almost see the cliche'd scene. Zoey with a black eye, saying: "But Louis has CHANGED! He won't beat me again! I know he won't!" And that in turn can only lead to the Jerry Springer episode, "I don't know who's worse to me - my boyfriend or the zombies!"
Oh yeah, I'm going to hell for sure. ;]
Edit: So, finished Death Toll. The bots, while usually competent, have this really @#$%ing annoying tendency to totally screw the pooch during the very last seconds of a crescendo event. Specifically, when the ride is within sight, they have this bizarre tendency to RUN AWAY FROM THE PICKUP POINT. I noticed this with the helicopter at Mercy Hospital, but I thought it was a fluke. Nuh-uh. They're doing this on purpose. When the radio said "two minutes until I'm there", I moved us all out of the house and down to the dock. We were doing fine (even took out a THIRD tank without much problem), and I saw the boat moving in fast. Looked back down the dock... Francis and Zoe have run off into the woods! They were right on the dock with me two seconds ago when I looked away to see the boat, and now they're GONE! They're not on the dock, they're not on the shore near the dock, they're not standing near the rock. They're so far out of sight I can't even see their blue silhouettes! How the hell did they run that far in two seconds? (I know what you're thinking, but it wasn't a smoker. I would have heard him.)
More importantly, WHY did they run away when the boat was so obviously coming? You can see it, you can hear it. Is the AI not bright enough to move towards the pickup point under those conditions? Especially if one of their teammates is already there?? I don't buy it. I think they're running away on purpose. Next time I see one of them running away from the pickup point right as our ride arrives, it won't be the zombies that get them - I guarantee you that. I'm getting to be a pretty good shot with the assault rifle, and putting half a clip into the back of their skull as they run the exact wrong direction (for no reason at all) will not be difficult.