In trying to figure out the most profitable monsters to raid, I got the bright idea to index the mean treasure values against the expected “difficulty” of the raid. I made a stab at doing this, and have bogged down. How do you determine how tough a bunch of monsters are?
Obviously this will depend hugely on the Dungeon Master, there aren’t really any rules in Dungeons & Dragons, there’s no such thing as an average party, etc. etc. But from a player’s point of view, sizing up your opponents is a problem of immediate application, especially in a West Marches style game where players can zip all over the landscape looking for (or hoping to avoid) certain enemies.
Aside from the de rigeur objections, there’s a ton of data about how hard monsters are to fight, at least in comparison to each other. We’ve got zillions of pages about various monsters, their hit dice and number appearing, their likely combat tactics, their special abilities and special defenses, and in some cases the conditions of their lairs.
My initial thought was to multiply average hit dice per average number appearing. It’s simple and sensible enough for “normal” monsters, and even kind of informative. For example, it suggests that a decent-sized lair of Orcs (35 @ 1 HD, plus about 5 HD of leaders; average gold per hit-dice of 100 gp) is considerably more trouble than a typical lair of Ogres (7 @ 4 HD; average gold per hit-dice of 71 gp), but more profitable too.*
Obviously the trouble would be how to account for special abilities. A Dragon Turtle (1 @ 30 HD) in its lair is certainly far tougher than a gang of Neanderthals (25 @ 2 HD, plus some leaders) in theirs.
I’m tempted to use XP values (conveniently listed for each monster in Mentzer BECMI) as a measure of toughness, which is somewhat better but still less than ideal as there are all kinds of weird results in Mentzer. For example, a 10 HD Red Dragon (AC -1, fire breath, three melee attacks, spells, flight) is worth 2300 XP, the same as a 13 HD Cyclops (AC 5, throw rocks, one melee attack, no depth perception).
Mentzer adopts a more convoluted approach in the Master Dungeon Master Guide, page 9, which I’ll simplify somewhat – feel free to seek out the source for fiddly details:
- Total up all the levels in the party.
- Total up all the monsters’ hit-dice. For each asterisk, add half the hit-dice. So a Red Dragon (10 HD**) would be worth 20 points.
- Compare the total levels. If the monsters’ total comes to less than 30% of the players’, then the encounter’s a distraction which mainly bleeds a few resources. If the monsters’ total is about 50% of the players’ levels, then the encounter is a decent fight. If it’s 70% of the players’ levels, then the encounter will be quite challenging, requiring good play and some luck to overcome. Up to 90% and it’s probably a climactic encounter which might skrag a character or two. Much higher than that, the encounter may prove totally overwhelming.
For reference to any Red Boxers reading this, the Grey Company in Tavis’s White Sandbox game typically fields at least eight PC’s, probably average level 4. This implies that we should be able to defeat that Red Dragon if we’re sharp. I have my doubts about that, but we should be able to kick a lone Cyclops’s ass without much trouble, and that sounds right to me.
I’ll fiddle with the numbers and see if anything ends up making an acceptable amount of sense.
Anyway, in the meantime: what’s the best way to determine how hard a fight should be?
* I’m tempted to rate all profitability in “Orc-loads,” referring to the approximately 100 gp per lair-hit-die as a standard unit of measurement. A single Kobold is 0.0114 Orc-loads.