Thursday, August 13, 2009

What if armor gave you hit points?

Clash's post about front loading, particularly the part about armor-as-damage-reduction, got me thinking. First it got me thinking that maybe my ignorance is my only strength, since it has never occured to me that armor doesn't make you harder to hit. Well, armor only exists in D&D as far as my experience goes, so what do I care. Never mind that. It also got me thinking of how that front loading might be made more back-loady by having armor grant hit points, leaving your AC at 9.

Following Delta's mechanic (d20+fighter level+AC>=20=WIN), a first-level non-fighter hits AC 9 on 11+ or 50% of the time. In OD&D average weapon damage is 3.5, so for 100 swings an unarmored combatant would, after waiting patiently to be swung at all afternoon, take 175 points of damage. I guess they used to call the damage hit points, but that will just confuse today's readers and I prefer to do that through garbled writing.

So, moving up the scale of armors, leather will protect you from 10% more blows, resulting in 140 damage on average--as savings of 35 hp. For chain the savings is 70, for plate 105. How's my math? That would make normal shields worth 17 or 18 hp, which pleases me as a convenient way for them to be rather quickly destroyed.

Now what do we do with these imaginary 100 blows? Is that a useful number? How many hit points should the armor provide over its life and the life of an adventurer? How about arbitrarily saying the armor is destroyed after 100 blows? Make it one hundred and one, as that's more folklorish.

Wait a minute, nobody's going to count 101 blows! They will of course be represented by the hit points. Whew. I almost missed that one.

Then again, nobody on the Mutant Earth is wearing any armor yet, and when they do it will probably be force fields, so I don't have a good (that is, requiring no extra work) way to try this idea out, not this week anyway. I'll put it in the hopper.


Jeff Rients said...

I think armor adding a pile of hit points can totally work. S. John Ross did it for his Encounter Critical text adventure game. At first it through me for a loop but it seemed to function just fine.

If tracking armor and personal hit points seperately I'd probably want to see some sort of critical hit mechanism that did damage to both armor and person.

Aaron Nuttall said...

Good idea, Jeff, about the critical hits. I think I'd go with 20's doing their regular damage to both, becaue that's obvious and easy.

I just realized it's silly to have a suit of plate mail with 1 hp. Maybe the armor should fail to protect more often when it gets below 50% and have a chance to become altogether useless.

I can see why the space adventurers always go with force fields--easier to model because they're made up.

Talysman said...

You inspired me to whip up my own houserules on armor reducing damage. I went with the idea of not tracking damage to armor, but just letting each blow have a chance to damage the armor.

Mark Hughes said...

That's what Palladium does.

The original Mechanoids Invasion trilogy just had a big pile of SDC to wear down.

Fantasy added the Armor Rating; an attack roll under AR hit the armor's SDC, so you could have sturdy but low-coverage armor or flimsy full suits. Monsters have AR but infinite SDC for it, so you don't have to track yet another number.

Rifts just has a big pile of MDC, because anyone not in full armor is gonna be vaporized by an explosion pretty quick.

The nice part of all of these is you have to repair your armor, and the very high cost of new armor encourages players to avoid heavy combat or at least make hard decisions.

JDJarvis said...

I've played in LARPs where armor was really just extra HP. Don't see why it wouldn't work in a tabletop game.

clovis said...

I use a simplier mechanic,

I have certain forms of armor
INCREASE you CON score;
therefore, not only are saving throws increased,
but hitpoints are increased,
the greater your level/ experience
the more your armor protects you . . .
after all, proper use of armor is a skill.

Aaron Nuttall said...

clovis: CON improves your saves? What game are you playin', whippersnapper?

Barking Alien said...

This isn't a new idea by any means. D&D armors always made you harder to hit, not harder to hurt (the opposite of real world armor which protects your body by forcing you to lug around wearing a metal suit).

I think the first time I saw armor work close to correctly IMO was Villains & Vigilantes (1982? 83?) where armor granted you Armor Protection Points that faded from said Armor each time it was hit.

R. Talsorian's games had armor loose points each time it was hit also, though usually only if the Armor failed to protect you (You have 5 armor, you're hit for 7 points of damage, you take 2 points and now your armor is 4). I might be a bit off on the exact specifics as its been a while.

Barking Alien