I have long felt that
posturing should hold a major place in "combat" -- with
cool-looking combat gear -- plumed helms, war standards, etc. -- made cool-looking specifically in order to be literally awesome.
Some enemies will fight to the death. The horde of zombies will keep coming until the PCs have defeated it; the construct guarding the crypt will not stop until it is a pile of rubble.
I keep returning to the idea of zombies taking "critical hits" when they "should" die -- but they keep coming, minus an arm, or while advancing up the shaft of the spear, etc.
Really, anything that keeps fighting
at all after getting wounded, when it could slink off, is pretty unusual. Berserkers should be scary not because they're using a special berserk-rage power, but because they're trying to kill you more than they're trying to stay alive.
There are four times as many orcs as PCs. At what point are they going to realize they're dropping like flies and their numbers are *not* an advantage this time?
If we take this outside our gaming experience, and we totally remove the expectation of a fight to the death, it's not clear that the orcs even attack in the first place. What do they think they're going to get out of it? And who wants to be the first orc to charge the great elf champion with the glowing sword?
In the source material (
Lord of the Rings), the orcs cower in fear of a single (assumed) great elf champion, a simple hobbit with a magic sword -- and, unknown to them, at least not consciously, a ring of power.
Anyway, if their sergeant yells, "C'mon you apes, you wanna live forever?" it's not clear that they then attack in good order. They probably start posturing -- yelling, smacking their shields with their weapons, stomping their feet, etc. If the other side doesn't turn and run, then they might start to wonder, "Who are these guys?"
If their leader motivates them, and they do charge, they expect the enemy to drop their shields, turn, and run. That's how you win a battle. If that doesn't happen, they might start wondering, "Are we going to win?" Guys in the back might be happy to stay there, and losing the front line without pushing the enemy back would be
bad news.
You wouldn't need anywhere near 50 percent casualties to trigger a rout. (I suppose proportions get a bit weird with only five or ten guys on a side though.)
So, I suspect you'd be best served by a morale system with
some numbers -- like an Intimidate skill with bonuses for cool-looking gear -- but with checks not-so-rigidly defined and results not so binary. Under 3E's rules, for instance, a successful intimidate check leaves the target
shaken for 1 round, when it should probably leave them
shaken indefinitely, potentially
frightened, and even
panicked.