I've mentioned it here before, but for those who have missed it I am currently running a Deathwatch game. The game is going along fairly well, and while it is a bit clunky, I think that is due to the fact that I have 8 players more than anything else. Anyhow, the last few missions in the game, things have been fairly straight forward. I haven't had much time to plan or prep with school, and so I've just thrown big monsters and some other straightforward enemies. You know the kind, the masses of zombies, the slavering beasts, the dumb brutes that good PCs just hack n' slash their way through, because that is what PCs do. However, this time next week I should be done with school forever, and with more time on my plate I think it's going to be time to bring in some smarter opposition.
Now, before I go any further, I feel I should point out that what works for my group may not work for your group. My group likes having a challenge beyond "can we get him to 0 HP before he gets us there?", and while those straight up, knock down fights can be good to have at times, all of us like it when we get to pit tactics against tactics on the field of combat. For that reason, and partially at the request of the players, I'll be bringing back the Tau, as well as some other 'smart' NPCs for them to fight.
So, what makes these NPCs so awesome?
#1 Planning and Ambushing
You can do this with any NPC, but when you are specifically bringing in a tactically smart NPC group, you get to do it a bit more, and that can be fun. Set some traps for the PCs, see if they walk into them and how they handle them. One of the awesome things about Deathwatch is that the PCs are strong enough that "just walk in and spring the trap" is a viable strategy for dealing with it. However, PCs are tricksy, and so once they see that you're being tricksy back you'll get to see them at their most paranoid. Is that a door? What if it has a melta bomb on the other side? Better check carefully...right?
These NPCs also let you start off the fights by ambushing the PCs, which can be a fun change of pace - and will also really up the paranoia on your players' part. Be careful not to go too nuts with this, but a sniper shot coming out of the blue and taking out a valued piece of equipment, or blasting an NPC in the head and killing it instantly to show that the enemy is willing to strike without warning can be a fun tool to use.
#2 Complex Goals
Once the enemy can think, their goals can be a loat broader. Maybe they're just looking to assess the group. Maybe they just want to see how well defended an area is, or how the opposition responds to a particular type of strike force. Maybe the enemy is there to plant something, or to extract something. The point being, you get to use goals that are more than just "kill everyone" and "fight to the last man, no matter what". Even better if your players need to find these goals out, and figure out why the enemy never sticks around to engage them for long before bugging out and going to ground.
#3 Complex Methods
Remember those traps and ambushes I mentioned before? Well, use them, and put the PCs on a timer at the same time. Say, for example, the PCs have fifteen hours to get from point A to point B. Along the way, the enemy has seeded a number of locations with traps and ambushes. The PCs are going to want to go slow and check things out. They definitely won't want to rush into life threatening situations. However, going slow means they will lose in the end. Now there is tension for just how fast should they go. Should they risk the injury to get the win? Or should they risk losing the big win, because if they're all shot to crap by the time they get there...well, it doesn't matter anyhow.
#4 It Gets Your Creativity Going
This isn't something directly in the game, but playing smart NPCs keeps your brain juices going, and that in turn can make you more creative all over the place. I, personally, like that. I like coming up with interesting solutions, interesting problems, and interesting characters and ideas. I find I do all of these a lot more when I get to plan for a smart enemy than when it is just the monster of the week.
There are plenty more reasons to enjoy a smart NPC (by all means, sound off on them in the comments) but those 4 are the big ones I like. I'm really looking forward to the next few sessions of Deathwatch and challenging my PCs with some more tactically thinking enemies. Maybe some PCs will die, with 8 players that's almost a given to happen at some time. Hopefully not as quickly as they might though, after all, the point here is to bring out their creative side too.