High HP and damage-based effects

[Taumaturgo]

I know that healing, crippling injuries and stun modifiers are proportional to maximum HP.

But there are other effects, like a Side Effect in a Innate Attack, or lethal electrical damage, that impose -1 to HT roll per 2 points of penetrating damage (in side effect) or injury (in electrical damage).

1) In electrical damage case, should I consider -1 per 4 points of injury for HP20-29 creatures; -1 per 6 points of injury for HP30-39 creatures, and so on?

So, if an elephant with HP45 is hit by a transmission line cable and takes 20 points of injury, should him makes a HT-10 or a HT-2 roll to avoid unconsciousness?

2) Side Effects and electrical damage work the same way, except for that one of them is penetrating damage-based, and the other is injury-based. This prevents me from create an Innate Attack that emulates perfectly an electrical damage. Is there any way to create an injury-based Side Effect?

[AlexanderHowl]

Yes, I think that effects should be proportional to HP (honestly, so should toxic damage, as you have to use a lot more toxin to even damage a larger creature, but that is the choice of individual GMs). I have asked for a ruling to change Side Effects from penetrating damage to injury, but they have not changed anything yet. Since it is less advantageous than standard side effects, I would reduce the base modifier from 50% to 25% for Injury-based Side Effects.

[Rupert]

Originally Posted by AlexanderHowl

Yes, I think that effects should be proportional to HP (honestly, so should toxic damage, as you have to use a lot more toxin to even damage a larger creature, but that is the choice of individual GMs).

It already is - larger creatures have more HP, so X damage is proportionally less damage to them. Also note that special effects from poisons and many other things are based on thresholds, and these automatically allow for large numbers of hit points.

Aside from the effects of Damage Reduction (from Powers), when it comes to electrical damage I'm not seeing a great difference between injury and penetrating damage (brain hits are the only thing that spring to mind). I suppose the rules allow tight-beam burning electricity, so you could also have attacks to the vitals, but we're not talking about something that behaves much like RL electricity at this point.

Also, why is it so important that a power perfectly replicates the rules of electricity rather than in all but one minor way? And if it bothers you, just change it for that one power.

[AlexanderHowl]

A creature with 20 HP possesses 8 times the mass of a creature with 10 HP, so they should require eight times as much poison as a 10 HP creature.

[sir_pudding]

Originally Posted by AlexanderHowl

A creature with 20 HP possesses 8 times the mass of a creature with 10 HP, so they should require eight times as much poison as a 10 HP creature.

I think if you tried to make everything that might scale linearly with mass scale linearly with quadratic HP you will have an unplayable mess.

Poisons that cause instant injuries of the sort that just do Toxic Damage aren't realistic anyway, so trying to make them behave "realistically" is a fool's errand.

For side effect Afflictions you can just apply the rule for SM and Afflictions.

[Taumaturgo]

Originally Posted by Rupert

Aside from the effects of Damage Reduction (from Powers), when it comes to electrical damage I'm not seeing a great difference between injury and penetrating damage (brain hits are the only thing that spring to mind). I suppose the rules allow tight-beam burning electricity, so you could also have attacks to the vitals, but we're not talking about something that behaves much like RL electricity at this point.

Also, why is it so important that a power perfectly replicates the rules of electricity rather than in all but one minor way? And if it bothers you, just change it for that one power.

This is the problem. I am using Powers and Supers, and there are a lot of characters with Damage Reduction and SM 0, and the diference between penetrating damage and injury is huge in this case. Actually, even without Damage Reduction, remains a big diference when using a Impaling Attack, or a Cutting Attack.

Originally Posted by AlexanderHowl

Yes, I think that effects should be proportional to HP (honestly, so should toxic damage, as you have to use a lot more toxin to even damage a larger creature, but that is the choice of individual GMs). I have asked for a ruling to change Side Effects from penetrating damage to injury, but they have not changed anything yet. Since it is less advantageous than standard side effects, I would reduce the base modifier from 50% to 25% for Injury-based Side Effects.

I'm not sure about Toxic damage, but I like the idea of reduce the modifier value. Or simply assume that in this campaign, all Side Effects are injury-based.

[Rupert]

Originally Posted by Taumaturgo

This is the problem. I am using Powers and Supers, and there are a lot of characters with Damage Reduction and SM 0, and the diference between penetrating damage and injury is huge in this case. Actually, even without Damage Reduction, remains a big diference when using a Impaling Attack, or a Cutting Attack.

Well, just rule that it's all by injury then.

[Taumaturgo]

Originally Posted by Rupert

Well, just rule that it's all by injury then.

Ok, but besides that, there is the problem with high HP and modifiers. The modifiers are proporcional? Even in realistic cases, like the elephant, use SM is not enough. An elephant have SM+3, so in the 20 point injury case, using -1 per 2 points of injury, the roll would be HT-7 (-10 due to injury and +3 due to SM). I tink its too hard to an elephant, since 20 pints of injury it's not even a major wound to him.

[Lord Azagthoth]

I always use percentages. a -1 for every 2 HP of injury (considering the system is meant for humans with 10 HP). So its -1 for every 20% of HP. Using the elephant as an example, with HP 45, it would be for every 9 points of injury. The 20 point injury would be a -3 instead of a -10 (unmodifed HT with the +3 for SM).

[Varyon]

Many things do make sense to be based on percentages rather than absolute value, and Side Effect is certainly one of those. Additionally, I agree that basing Side Effect on Injury probably makes more sense than basing it on penetrating damage - particularly because this makes the price difference for adding it to different damage types (the base +50% for Side Effect costs [1.5] for Pi-, [2.5] for Cr/Pi, [3.5] for Cut/Pi+, and [4] for Imp/Pi++) actually make some sense. It does mean my scheme of replacing Affliction with Side Effect with No Wounding wouldn't work, although in theory you could say that when No Wounding is in effect you base it on nominal Injury (that is, what the Injury would be if you didn't have No Wounding).

For poisons, GURPS doesn't typically handle those that realistically (although typically more realistically than other systems). For example, I think every +1 SM doubles the amount of poison you need to use to get a "dose," for a progression of 1, 2, 4, 8, 16, etc, while mass follows a progression of 1, 3, 10, 30, 100, etc. You could probably get direct-damage poisons working with mass fairly readily - just require it to scale linearly, then make damage percentage-based with an option to roll dice for variance (simply multiply the die roll result by 10%, and this is the percentage of the target's HP that is dealt), but the effect of using a different than nominal dosage is going to be a bit hairy.