Why a 20-die cap on falling damage?

[Staffan]

I think skydivers get higher speeds on account of (a) trying to minimize air resistance (hence the "diving" part) and (b) doing it at high altitudes where there's less air and thus less resistance.

As an aside, Spelljammer added rules for burning up on re-entry into the atmosphere

 

[dcollins]

The 20d6 limit is a historical constant since 1st Ed. AD&D, intended to give characters some survival chance when falling from great heaights (AD&D 1E PHB p. 105). Since PC hit points have inflated dramatically since that time, it looks a little bit out of place now.

The book Skydiving by Bud Sellick stipulates that terminal velocity is reached after a free fall of some 1500 feet (12 seconds), at a speed of about 174 ft/sec. This is based on a 200-pound person falling from 2,200 feet. It's slightly less at a lower height (160 ft/sec terminal from 1,000 ft high). It may be significantly more at a very great height (235 ft/sec from 30,000 feet).

I'll also mention that the 20d6 falling damage limit, and the on-paper ability of fighter PCs to survive falls from any height, was basically the reason thar 2nd Ed. came up with the "death from massive damage" rule, that really doesn't fit in well with the rest of the rules, and plenty of people don't realize is core. They'd be better off to just increase the falling damage. (IMC, I house rule away the massive-damage rule, and use Gygaxian geometric falling damage instead.)

 

[James McMurray]

In a world where cheetahs can go from full tilt run to dead stop in an instant, and where anyone whose lived a life of adventure for over two years (i.e. is a 10th+ level character) can survive being immersed in lava for 6 seconds, cannot be said to follow the laws of physics. Attempting to apply terminal velocity and constant falling acceleration rules to such a universe is (IMO) silly.

People wanting a realistic falling system should check out Rolemaster (second edition is best). There whenever you fall you get to roll on the incredibly nasty Fall/Crush chart with a bonus to the die roll equal to the height you fell. Odds are you were going to be pretty hurt after even a modest fall.

 

[Ridley's Cohort]

I agree with James.

If you can accept surviving a 100' drop, why not 1000'? There is no God of Realism forcing you to obliterate the PC in either of these two cases, when you might let a PC survive a dragon breath while caught in its mouth.

 

[dvvega]

Terminal Velocity is subjective. The average skydiver is not trying to increase his air resistance most of the time. They reach terminal velocity much faster than someone trying to resist falling.

Normally when a human falls we flail our arms about ... think abut when you were a kid on a trampoline and went high ... you would flap to try to keep your balance and slow your descent a little (even if it was instinctive). It is assumed (in d20 and other games) that you are trying to minimise your impact in whatever manner you can. This means terminal velocity is reached much later.

Real world example: skydiver going into arrow mode vs spreading himself out and "hovering" for acrobatic maneuvers etc.

 

[Oldtimer]

In previous editions of the game, one suggested system was:

Height/ Damage

10'= 1d6
20'= 3d6
30'= 6d6
40'= 10d6
50'= 15d6
60'= 21d6

Which was extremely silly. Why should damage not be proprotional to distance fallen? If anything, it should be less than proportional as air resistance increases with speed.

1d6 per 10' fallen is good enough. And with the ability to reduce damage with Jump or Tumble, you can actually use a parachute without taking damage.

/Mikael

 

[uzagi_akimbo]

Actually - imagine the following scenario - the hefty fighter (say 250lbs including armour etc ) falls of the 60' high castle wall in midfight, "bounces" , well comes to a "full stop" on the courtyard flagstones, and scrapes off the 21 points of damage (on average (6D6 = 6x 3,5 damage).... no sweat. That would be by standard 3.5 rules.

Now please picture the same fighter standing at the foot of the same wall and being struck by something else of similar density and size dropped from 60' above( aka the top of the wall) smack onto him ( say, like 2 bags of powdered concrete/flour etc ). Any (?) GM would definitely apply more than a meagre 6d6 of damage to him.
But purely from a physical point of view it does not really make a difference in the energy exchanged/transfered if an object of equal mass does strike you at a certain velocity or if you strike it ... Trauma, shock and injuries/damage should be approximately the same - random factors like location excluded.

Therefore - as a personal measure/houserule - I am using 1D12/10' fallen (instead of 1D6/10') as damage in my own campaigns, with a Reflex-based save (DC=# of feet fallen) for half damage, alternately a tumble check may be applied (same DC)). Also, the character is prone , disoriented and stunned for 1d10 rounds / 10 points of damage taken. This does allow for an IMHO acceptable degree of respect towards drops, but also allows a chance for a lucky escape.. In any case, a character being dropped from a great height is out of the combat - but not necessarily out of the adventure.

uzagi_akimbo
Higher being in charge of sudden, unexpected and totally improvised Doom

 

[Gnimish88]

Actually - imagine the following scenario - the hefty fighter (say 250lbs including armour etc ) falls of the 60' high castle wall in midfight, "bounces" , well comes to a "full stop" on the courtyard flagstones, and scrapes off the 21 points of damage (on average (6D6 = 6x 3,5 damage).... no sweat. That would be by standard 3.5 rules.

Now please picture the same fighter standing at the foot of the same wall and being struck by something else of similar density and size dropped from 60' above( aka the top of the wall) smack onto him ( say, like 2 bags of powdered concrete/flour etc ). Any (?) GM would definitely apply more than a meagre 6d6 of damage to him.
But purely from a physcial point of of view it does not really make a difference if an object of equal mass does strike you at a certain velocity or if you strike it ... Trauma, shock and injuries/damage should be approximately the same - random factors like location iexcluded.
uzagi_akimbo
Higher being in charge of sudden, unexpected and totally improvised sudden Doom

Ah, but with the way hit points work in D&D, the 2 bags of flour nailed the 1st level fighter dead on, whereas at 10th level, he got almost completely out of the way. On an amusing note, if you apply this to falling, you could say that characters get better at missing the ground as they increase in levels...

 

[dcollins]

Which was extremely silly. Why should damage not be proprotional to distance fallen? If anything, it should be less than proportional as air resistance increases with speed.

Because falling damage is presumably not "dodgeable", like combat blows, arrows, etc. Geometric falling (and environmental) damage serves to countebalance the fact that higher hit points become more dodging/metaphysical, and less actual physical firmness. Likewise, cinematically it's easy to rationalize being near-missed in combat, but it's very hard to visualize people intentionally diving off 100 ft. cliffs onto rock (or surviving for days floating in arctic waters).

More: www.superdan.net/environs.html

 

[Plane Sailing]

Why is there a 20 die limit on falling damage? Why does a fall from 300 feet not do 30d6 damage?

To take a completely different tack - D&D tends to "top out" at 20d6 damage in several places (falling damage and immersion in lava are the two that come to mind).

It looks a little like a design decision somewhere where someone said "OK, whats the biggest amount of damage from a single natural effect? What would falling from 1000ft do, or being immersed in lava?"