The morale mechanic has apparently fallen out of favor in later editions of D&D. I could paw through different books and the intertubes to find the exact edition where it went away, but that's not really what I'm interested in talking about. Rather, I'd like to talk a bit about how it is employed in many classic RPGs like B/X and why, in my oh-so-humble opinion, it is a very good thing.
First off, I should mention that the morale rules in Moldvay (B27) are expressly listed as optional. The game can be played without them. In my experience,they add a level of realism and survivability to the game that makes them more than worthwhile. Let's take a quick look at the opening lines of the section:
Any creature in battle may try to run away or surrender. Characters are never forced to do this; a character always reacts in the way the player wishes. NPCs and monsters, however, may decide to run away or surrender.Two main takeaways to consider here:
1) "Characters react in the way the player wishes." There are things like fear spells and effects (Giant Shrews, anyone?) that can effect a PC, but whether to fight on in the face of dire odds is completely in the hands of the players.
2) "Any creature in battle may try to run away or surrender." This is an element of morale that I don't always remember to apply. I usually just have a creature run away if it fails its roll. That's fine for dumb beasts, but an intelligent creature may throw in the towel (especially is escape looks unlikely).This can lead to fun RP between the victors and the vanquished, not to mention alignment considerations by the players.
Remember how a decent charisma score can be a boon not only when hiring retainers (reaction rolls) but in giving them better morale? Here's a fun one: NPCs could decide to surrender to the bad guys if the PCs are losing a fight (or look like they might lose)! They might even switch sides! Weirdly, a counter-argument for not having all the hirelings just work for the one charismatic PC. If the NPCs are loyal to different PCs, that should mean separate morale rolls, which means it's not all or nothing when checking morale. Some minions might break while others remain.
I mentioned realism and survivability. It seems perfectly realistic than not every encounter ends up a fight to the death. Sometimes nerves fail. Even a bestial predator may decide the PCs are not such an easy meal and take to its heels. BX gets a rep for being fairly lethal. Using morale in your game means some fights end a little sooner, which means fewer to-hit rolls against the PCs, thus less damage taken and fewer casualties.
