4E's hit point philosophy

[tbone]

Originally Posted by Polydamas

So after 20-26 hits from a light gun she is in danger of sinking. Halve that if damage is doubled for pi++. In the real world it took hundreds of hits to endanger such a warship, barring bad luck such as a fire or a powder explosion.

Thanks, that's a big help in understanding the discussion.

Let me try the same with numbers provided by the good Mr Icelander:

I'll attack the DR 6, HP 268 frigate with the 18-lb. cannon (it's not a huge ship, so I'll stick to a mid-size gun).

7dx4 dam generates an average 98 basic hits. Looking at just basic hits without any complications, we subtract DR 6 for 92 basic hits... meaning the frigate is at negative HP after 3(!) cannon balls. Yikes, am I doing that right??

Let's try the 4d+2 musket. Average damage 16 - DR 6 = 10 hits. That means the frigate is at negative HP after 27 musket shots. (If I'm doing things right.) Clearly the task takes many more musket balls than cannon balls, as should be the case, but yeah, I'd have to say that either weapon seems to make oddly short work of a ship.

Hmm. Knowing little of GURPS guns-vs-vehicles mayhem, and even less of the real-life equivalents, I'll crit miss a Will roll vs Obsession (Must. Think. Of. Rules.), blather something silly, and move along.

1) If the basic GURPS 4e approach is to abstract vehicles and other structures into a simple DR + HP approach, the same as with creatures, I think that's cool. That is, it'd be great if there were also a 3e Vehicles-like approach with detailed thickness-based DR and materials-based HP and substructures and all that – but as the default system for gamers who may not care about detailed structural stuff, I'm all for an approach of "A tank has DR X, HP Y. Game it more or less like a character."

2) That said, it would be nice if the abstract DR and HP of such structures scaled in a way such that canonical examples, like big guns vs pirate ships, fall within the ballpark of feeling reasonable. Based on what people are saying, it seems DR and HP should scale up much higher for big structures. With a big wooden ship, for example, DR should arguably be high enough that musket fire has no effect.

3) Oh no, here comes the "gotta make a rules suggestion" part: It seems sensible to set abstract ship DR high enough that small arms have no effect... and yet, saying "Muskets can't do anything. Sorry." isn't entirely satisfying either. If ship stats were gamed in great detail, musket users could avoid the hull and big structures, and pick out some smaller, weaker targets in order to do some damage (if not much). Using simple and abstract vehicle stats, maybe we could simulate picking away at weaker locations with something like this (vaguely similar in concept to chinks in armor):

To aim at substructures or other less-important parts, take -X TH. Success divides DR by X, but also divides post-DR damage by X^2.

Example: Say the frigate had abstract DR 24, not 6. Musket fire (av. 16 basic hits) would be ineffective. But musketeers could aim at ropes, deck structures, open ports, etc.: for -2 TH, divide DR by 2, divide post-DR dam by 4. Average damage = 16 - 12 = 4; 4 / 4 = 1.

So, an effective 1 dam per hit. If the frigate also had better-scaling HP (500? 1000?) then maybe that damage is approaching reasonable? It's markedly smaller than the 98 hits - DR 24 = 74 hits of the 18-kb. cannon...


Ok, done. Itch scratched. Thanks, and sorry –