One of my current pet D&D 4E projects is coming up with random encounter charts for exploration in the Nentir Vale. As I was flipping through my Monster Vaults and MM3, I was a bit overwhelmed. My first thought was that I was going to have to wind up creating hundreds of different little groups of monsters that would probably never get used. Seemed like an awful lot of work for very little reward, so I didn't get very far in that endeavor. However, I really want to implement a wandering monster/random encounter mechanic for my kids' 4E game.
And then today, I had an epiphany. Over at the Blog of Holding, Paul wrote up the Monster Manual 3 on a Business Card, which very effectively and concisely boils down the math for D&D 4E monsters. Obviously, a lot of monsters have more to them than just hit points, armor class and defenses, and damage, but for quick and dirty encounters without paging through the books, it works like a charm. You really only need one monster in any given encounter that has abilities that inflict status effects or do other cool stuff (any more than that becomes tedious), and it's usually pretty easy to keep the book open to that one monster. So, this occurred to me: use the MM3 on a Business Card for the basis of my random encounters. Kind of like this:
If you roll for a random wilderness encounter, roll 2d10 and add the numbers together, and:
C = # of characters in party
L = avg party level
2 Unique NPC/Monster from this area
3 Unique NPC/Monster from this area
4 Elite Controller +2d6 2-hit minions @ L+1d6
5 3 Soldiers @ L+1d6
6 5 Soldiers @ L-1d6
7 Brute and 2 Artillery @ L+2d4
8 3 Brutes @ L-1d6
9 2 Lurkers @ L+1d6
10 C+2d6 minions @ L+1d6
11 C+1d8 minions @ L-1d4
12 C+1d6 2-hit minions @ L+1d4
13 C+1d4 artillery @ L+1d4
14 Brute and 2 Artillery @ L-1d4
15 Controller, Soldier, 3 Minions, Brute @ L+1d3
16 Solo Soldier @ L+1d6
17 Solo Brute @ L+1d6
18 Solo Skirmisher @ L+1d6
19 Unique NPC/Monster from this area
20 Unique NPC/Monster from another nearby area
You'll notice that I grouped the minion encounters in the middle, so they will be most common. I also used only the "role" name for opponents. This leaves all the description and detail in the DM court, while still having random possibilities. The band of orcs attacking the party could be a bunch of ne'er-do-well punk minions (11) or they could be a bad-ass group of seasoned veteran warriors (15).
This obviously requires a bit more work on the part of the DM to actually make it work. For example, it would probably help to know just what types of different monsters are in the area that the PCs are traveling through. Hell, you could even make a list keyed to another random chart to see which species of monster is attacking. It would also help to have a list of the major unique monsters in the area (any big nasty dragons around? because that's what I would use on a roll of 2 or 20).
This is really just the tip of the iceberg. With a few rolls, you can have an interesting random encounter with whatever local monsters are appropriate. I'm thinking a table for some possible interesting terrain, as well as a type of encounter. What are the monsters and heroes doing? Do they just stumble across each other? Have the monsters been tracking the heroes? Do the monsters have a trap set for whenever wandering heroes come along?
The table above was just an example, but there's no reason you couldn't put specific creatures from the Monster Vaults in there, as well. If you're in the Old Hills in the Nentir Vale, there's no reason that #14 couldn't be a Blackfang Feaster (Threats to the Nentir Vale p.25) and two gnoll spearthrowers (statted up using the MM3 on a Business Card). In fact, using the MM3 on a Business Card, it's pretty easy to level the Blackfang Feaster up or down to taste.
Anyway, I think this will be the start of my template for moving forward with random encounter charts throughout the entirety of the Nentir Vale. I'll probably have the tables figured up a little bit differently for each region, but I think they'll work out okay. And yes, I'll start publishing them here as soon as I get them figured out.