Tuesday, July 8, 2014

Inevitable Damage Rules

The way I see it:

So, HP represents your ability to dodge, deflect, and soak up blows in combat.  And nearly everything does HP damage.  But certain types of damage bypass that system entirely.  It doesn't matter how much HP you have—if you are shoved off a 20' building, you are going to be injured.  Same thing if you are submerged in acid.  Skill cannot help you.  Your levels cannot help you.

So here is a system to model that.

So a few days ago I posted a Death and Dismemberment table designed to give injuries when a character took more damage than their HP could handle.  Here's a slightly newer one with a few more tweaks and polish.

The important things to look at are the numbers along the left hand side, the Severity, which are normally generated by rolling 1d8 + lethal damage (i.e. damage in excess of HP).
click me

It is possible for an attack to deal 5 damage that is both HP and Inevitable.  It's also possible for an attack to deal only one or the other.

The vast bulk of all damage will be HP damage, which works exactly as you are familiar with.

Inevitable damage means that you are guaranteed an Injury with a Severity at least equal to the Inevitable damage (on the Death and Dismemberment table, above).  This is true even if you wouldn't normally get any Injuries, or took no HP damage at all.

Important consequence of this rule: if a character ever takes 13 or more Inevitable damage at once, they're dead, regardless of HP.


Falls deal 1d6 HP damage for every 10' fallen and an equal amount of Inevitable damage (see below).

Jumping down from a height doesn't deal any HP damage, but you do take 1d6 Inevitable damage for every 10' fallen.  If you hang off a ledge and then drop down, treat the fall as if it were 10' shorter.  If you make a Dexterity Test, treat the fall as if it were 10' shorter.


A character with lots of HP falls down a 40' pit and takes 14 damage.  Normally, the character's HP would soak up the damage with no ill effect, but because fall damage is always Inevitable Damage, it is exactly as if the character had rolled on the Injury Table and gotten a Severity of 14 (dead).

A character jumps off a 10' ledge and fails their Dexterity Test.  Because they intentionally jumped (and weren't pushed) they take no HP damage, but they do take 1d6 Inevitable damage.  So, even though their HP doesn't fall, they have a equal chances of

  • landing prone
  • disabling a foot/leg for 1 day (possibly an impacted heel?)
  • disabling a foot/leg for 2d6 days (a rolled ankle?)

This hasn't been playtested yet, but I intend to write up some rules for Inevitable burns and sneak attacks and whatever.  Does this look sane?  Does it look too complex?  Does it look fun?


  1. The only thing I think I'll want to add is a way for wounds to become infected. I'm sure that I'll end up doing a save vs. poison or contract acute blood disease (I'm using AD&D1E), but I'll just have to work out a good way to determine when to roll the save.

  2. Inevitable damage reminds me of aggravated damage from Vampire.

    I am not entirely following how it is determined though. Does each effect, danger, and attack need to list the potential for inevitable damage?

    1. What Brendan asked: when does this actually apply?


      I'm assuming InDam isn't actually tracked and resolved like HP, just used to reference the lookup chart.

      "sub-zero" on the chart means what? Like x-naught/x sub 0? If so, I get you, but if that's meant as a handout, I feel like that's pretty specialized language

      It's interesting that you went with mechanical effects largely independent of the fiction. A. why did you do that? and B. I'm interested in how that plays out.

      This feels at least a little similar to Apocalypse World's countdown clock/health/healing/dying/damage mechanic(s).

    2. Something is either inevitable damage or it isn't. So if you take 1 inevitable damage from a fall, you look it up and see that you're going to land prone. But, if it's lethal damage (damage in excess of your HP), you also roll a 1d12 and add the lethal damage, which may be more or less than the inevitable damage number.

      Inevitable damage only exists because I didn't want high level players taking 50' falls and walking away shrugging.

      Now, a year later, I don't think I like inevitable damage any more. I don't need that much grit in my game.

  3. How about an attack that forces a Death and Dismemberment roll if it puts you below X HP? This is similar to the high-damage rule in 2E D&D where if you took 50 HP or more at once you had to save vs. death. Or maybe I'm remembering it from somewhere else?

    Anyway, the attack would be noted as doing damage of, say, "3d6 (DD30)" which means if you're dropped to 30 HP or below you must roll on the table.

    This leaves some powerful characters immune to the Inevitable roll, because c'mon being a Superhero/Necromancer should mean you're fine falling into a 10' pit. At least until they're worn down. I could imagine a villain fleeing through his secret tunnel and falling into one of his own pit traps by accident, and if he were fully healed up and refreshed he'd have no problem, but if he were tired / hurt he might have to roll on the DD table.

    In general, I feel like maybe you'd be happier with a generally low-HP game. D&D models different styles at different levels, so while it's gritty at level 1-3 it becomes more like playing Batman at level 9 and by level 14 it's more like Spiderman. If you want people to get hurt real bad falling into 10' pits, maybe run something like the 3rd edition E6 where characters cannot rise above level 6 and instead accumulate more feats as they gain XP?

  4. I like this and may try it out, although one thing I might do differently is to adjust the lethal damage die according to CON (and perhaps extend the severity range 1-18). Like so:

    18 CON - no added die roll
    16-17 +d2
    14-15 +d4
    12-13 +d6
    10-11 +d8
    8-9 + d10
    6-7 +d12

    For falling damage I wouldn't change anything since the player already gets a DEX save.