Why You Should be Using D6 Hit Dice

If there's one thing I like about the mechanics of your OD&D/LBB derived games, like FMAG and Whitehack, it's this: the humble d6 hit die. Just in case you're not aware of the difference: in B/X and onward, class's hit dice can be d4, d6, d8, etc., but they always gain one every level. All monster hit dice are given in d8s. In the LBB derived games, all hit dice are d6, for monster and player alike. Different classes just gain additional hit dice at different rates.

So why does this matter at all? First, it makes for slightly less "swingy" damage rolls. The worst case for a damage roll against a 1 HD enemy is that you rolled your minimum, i.e. 1, and the enemy has the max health for their HD. So, would you rather be reducing an enemy by 1/6 or by 1/8 at worst? Seems small, but certainly lessens the sting of rolling low on your damage.

But really, that's peanuts compared to the real advantage. And that advantage is reaped by you, the intrepid referee. And advantages reaped by you will, if all goes smoothly, carry over to your players as well, through smoother combat with less number crunching and note taking. 

Quite simply, rolling a fistful of d6s, and quickly sliding them into groups is much, much faster than rolling a d8 over and over again, adding it up in your head, and then noting that number down. For example, my party once ambushed six 3HD harpies in their nest. So, I grabbed 18 dice, rolled em all, and then quickly arranged them into six equal piles on my desk (without looking at the numbers too much). And that's it! I track the six harpies that way, knock off dice (or take a second to rotate one) as damage is done, and I never bother to write anything down. I almost always finish my piles before the players are done rolling initiative.

Overall, a pretty strong flock. There's clearly two stronger bosses, but there's not any single pushover.

As an added bonus, I don't even have to add the rolled hit die together. I also like to use pip dice so I can tell at a glance if I got a strong roll or not. 

It helps to have one of these big Chessex blocks of d6s as well. Since every layer of dice is nine, I can quickly grab large numbers accurately. If I need 16 dice, that's one layer, then six more dice.

I'm not the most experienced referee in the world here, but for the last sixteen sessions of my quarantine game, I've used this workflow for enemy tracking in my game quite smoothly. I have completely abandoned using the provided HP rolls in modules I use, since they're done using d8s anyway, and the extra randomness can add fun and flavor. I definitely did this when rolling with d8s in the past, but I like it when a random monster rolls the highest, and they are then the boss of the other ones. It's just faster to make those snap, emergent descriptions with this method.

Maybe someone else finds this useful. Of course, maybe this only works for me because my own brain's idiosyncrasies.

There is one other reason I'd like this to spread though: I think there's some untapped design space here. Having HP represented by dice adds another dimension beyond a flat number. This has been mostly untested by me, but when my players want to, say, chop off a troll's arm, or generally give a disadvantage to an enemy by hurting them in a specific way, I can determine that by seeing if their damage roll beats the highest die in a monster's hit die pool. If so, they can maybe take away one of a monster's attacks along with just the highest die.

I really do mean mostly untested though. This hasn't come up much so far. But there's a whole dimension to use here, and if you're already stuck rolling out a monsters HP, it doesn't have to add any extra note keeping.

Some other ideas for using individual hit dice in battle:

-The HD-derived stats of monsters go down as they lose HD from their pile. Monsters get worse at hitting and saving, maybe even losing attacks as their whittled down.
-A monster regenerates by re-rolling it's remaining hit dice every round. It's only permanently damaged by removing a die from the pile.
-Damage resistance being modeled by not doing damage unless the damage roll is higher than any rolled die, in which case it is removed.