For me, the hardest thing about running a sandbox game is making interesting decisions on the fly. What’s over that hill? What’s this plant do if I eat it? What’s that ugly orc thinking?

I can make something up, of course. But my made-up answers tend to be same-y, or simply not believable. It’s a tricky nut to crack.

I’m still working thru my answers to those first two questions. Recently, however, I realized a partial answer for the third: What is that monster thinking? Or, perhaps more relevant, what’s that monster likely to do? What’s his personality like?

Most OSR games answer this question two ways: A text blurb describing the monster, and a Morale stat to indicate how brave the monster is in combat. Both answers are inadequate.

The text blurb has two problems: It’s hard to digest quickly when flipping thru a statblock, and it doesn’t account for variation between the monsters. Sure, goblins in general might be vicious little opportunists, but what’s this goblin like? Is he pure aggro, or does cowardice come uppermost? Of course, the GM can make those calls on a case-by-case basis, but I have the aforementioned fear of same-y mobs and boring situations. Furthermore, many OSR GMs right want the the dice to make those calls.

The Morale stat’s usefulness is more obviously limited. It tells you what a monster does in combat, but that’s about all. It does nothing to tell you what the monster might do when negotiating with players; how long their friendship might last; or anything else not related to the shedding of blood.

My draft answer to this is a rule I’m calling Wickedness. All potential enemies have a Wickedness modifier. The higher the modifier, the greater their wickedness. Here’s the draft text I wrote up to explain this:

Wickedness

d6+Wickedness	Personality
0 or less	Friendly
1	Indifferent
2	Territorial
3	Mercenary
4	Backstabbing
5	Predatory
6 or more	Blood-crazed

All enemies have a Wickedness statistic, which indicates how their Personalities are inclined. More wicked creatures are more likely to have “bad personalities”. Note that personality does not replace reaction rolls; it will, however, modify their results.

GMs should be creative when interpreting Personality results: A “backstabbing” serpent might simply keep its distance until its victim turns its back; a backstabbing Slonovi mercenary might befriend the party over a period of weeks before suddenly turning on them in the night.

Personality results skew negative. For this reason, good or neutral creatures usually have Wickedness “penalties”: A peaceful monk might have a Wickedness modifier of –3; a common animal –2, or an opportunistic bear –1. On the other hand, wicked or aggressive creatures have Wickedness “bonuses”: A +0 for an irritable python; +1 for a triggerhappy soldier; or even +2 or +3 for a demon or hardened killer.

A quick example is in order: Suppose the party encounters a fellow adventuring band—of zombies, led by a red-robed necromancer! But while this necromancer is exceedingly evil, she’s not necessarily violent: Wickedness +1, perfect for a cautious sort of villain. Before the party says a word, the GM rolls to determine her personality:

d6+1=5, Predatory

While the necromancer might not attack instantly, she’s clearly ready to crack some heads. Perhaps her current minions are missing a few too many limbs, and she’s ready to replenish her squadron? Whatever her reasons, it’s clear our heroes will soon be defending themselves against an undead onslaught!

This rule does have one flaw: it can’t immediately be related to existing OD&D/BD&D/AD&D monsters. I’m still working out this issue: If you have any suggestions, please let me know in the comments!