I like that! What do you think for the xdx damage? To have enough resonance notes to use the ability, a caprine would need 18 HD (if I recall the max notes rule correctly), so how about 2d8 per round? That would give it a reasonable chance of killing another caprine of the same level, just as a reference point.
So 90 damage over the entire minute? A caprine of that level with the basic Con 12 would have 18d8+18 Hit Dice for 99 hit points, bur would likely have a better Constitution than that, for another 18 hp per point of Con bonus. It could also receive healing during the 10 rounds. I'd think it'd have fair odds of being at positive HP and making its saving throw when the time comes.
Let's see, the Resonance Working Draft
caps Resonance at five times HD plus ability score (CHA or CON), which is…
Hold on, ability score
? Should that be ability bonus
? One interpretation of that would suggest a very ordinary 8th level caprine would be able to use Sound of Death: 5 × (HD 8 + Cha 13) = 5 × 21 = 105 max resonance. That's assuming the caprine doesn't use its ability advancements on its resonance stats.
Or did we mean ability score plus quintuple HD, which, as you figure above, would require around 18 HD to use Sound of Death: Cha 13 + (5 × HD 18) = 13 + 90 = 103 max resonance.
Perhaps we should rephrase that to be clearer?
How about "The maximum number of resonance notes a caprine can sustain at any one time is equal to its Charisma or Constitution score (whichever is higher), plus 5 notes for each of the caprine's Hit Dice."?
I think we discussed using a formula based on Hit Dice multipled by the number based on the caprine's ability modifier, but decided that would make the influence of the Hit Dice too heavy, since the caprine adds its Cha or Con modifier for every HD. I guess one could express that using "The maximum number of resonance notes a caprine can sustain at any one time is equal to its Hit Dice multiplied by (5 plus its Charisma or Constitution modifier, whichever is higher, minimum multiple is 1)."
For example, with the HD × (5 + ability modifier) formula a sound of death
is achievable by a Charisma 13 caprine with 17 Hit Dice: 17 × (5 + 1) = 17 × 6 = 102 max resonance, but a caprine with Charisma 20 only needs 11 Hit Dice: 11 × (5+5) = 11 × 10 = 110 max resonance.
For contrast, a 12 HD Charisma 20 caprine would have an 80 notes max resonance with the "abilityscore+(5×HD) formula" and a 120 notes max resonance with "HD×(5+abilitymod)".
Want to do something funny like give a target a saving throw bonus based on hp remaining or something?
That might give a creature with piles of hit points a large advantage, especially considering such creatures would have good Fortitude saves in the first place.
A more serious restriction is that, as written, the targets must remain within 40 feet of the caprine for the entire 10 round music session to risk death from the sound.
That seems unlikely. So I'm thinking maybe a target must be within 40 feet to start
the deadly resonance, but after that it merely needs to be within earshot of the caprine for the deadly resonances to continue. Maybe a 300 ft. spread like the Captivating Song of a Harpy
Sound of Death #3: A caprine with a resonance score of 101 or more can play a terrible cacophany on a musical instrument that lasts 10 rounds. This heart-wrenching sound starts harmful vibrations in any living creature who hears the tune and is within 40 feet of the caprine when it starts to play. The caprine can tune sound of death so it affects or spares particular creatures, specifying what individuals, races or species the sound harms or does not harm. At the end of each round, the caprine takes 1d8 [?] hit points of damage, and all creatures affected by the sound's initial vibrations that are within earshot of the tune (a 300 ft. spread) take #d# damage [?]. However, this damage cannot reduce the affected creature below 0 hit points. At the end of the final tenth round, all creatures affected by sound of death (apart from the caprine) will automatically die (no save) if they are at 0 or negative hit points, or die if they fail a Fortitude saving throw (DC 10 plus half the caprine's HD plus its Charisma modifier) if they have positive hit points.
If the caprine is forced to stop playing the sound of death before the tune finished on the 10th round, the caprine takes 1d3 Constitution drain damage with no saving throw.
Sound of Death is a sonic death effect.
What action does the caprine need to use to continue playing the sound? If it's a standard action, that's a crippling problem for high-level combat, so I'm thinking maybe we should make it a swift or free action to continue the tune once it's begun (which'd presumably require a standard action).
Plus there's the "what can the Bard do" question.