There’s a big combat against a large number of lower-level opponents, and the PCs are triumphant (yay!) and there’s just mopping up to do.
Trouble is, they just can’t seem to do the mopping up. All they need is for one or two of them to roll something higher than a 10 “to hit”, and more than a 1 on damage, but they just can’t seal the deal. Their dice are laughing their asses off, as they roll an endless supply of 3’s and 4’s, round after round. Finally, someone mercifully rolls something with double digits, and the last skeleton is finally vanquished.
First of all, it’s ridiculous. You can dispatch 12 zombies in two minutes, but that last super-zombie keeps bobbing and weaving for five minutes while four trained warriors keep swishing? Bah.
Secondly, it’s tedious. Everybody knows the inevitable outcome. Is it really worth going through the aggravation of rolling all those dice over and over just to see if the cleric takes another 3 h.p. of damage before the last orc goes down? FOR THE LOVE OF THOR, JUST ROLL A 14!
When presented with this scenario, I’ll just say “you kill it” and move on. But there’s another alternative.
It should be possible to come up with a simple table for such (relatively) low-level mooks. Spare us the tedium of rolling over and over just to hit the magic 14; if there’s a mook with X hit dice, and the party has Y levels or armor class, someone takes Z damage (some piddling amount, if any) and we move on to greener pastures.
I’d still leave it up to the GM to implement; basically it’s a way to justify taking a hit point or three off without the bored “fine, let me roll a d20 yet again” to play it out. The percentages aren’t that hard to work out; the basic idea’s been around since Chainmail.
But man, I hate when that happens. Just want to finish it without such a blatant “the GM is bored now” finale.