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Message: <blockquote data-quote="Loonook" data-source="post: 5882171" data-attributes="member: 1861">I did the math for the valuation of the substance... Now, we can look into the basics of BTUs of open flames and immolation.Now, let us take the options of various heats.  A British Thermal Unit is the amount of energy required to make 1 g of pure water raise temperature by 1 degree Centigrade.  Full-body immolation occurs ~ 740 C, and the <a href="http://www.nist.gov/fire/fire_behavior.cfm" target="_blank">flashpoint of human skin is around 162 F (72 C)</a>.  The average starting temperature of the human body would be ~ 37 C. Human flesh, being made mostly of water, would 'boil' its reserves at 212 F (100 C), leaving behind crisp flesh. Now we need to deliver heat to the body at a rate to do serious damage.  Let us say that we want to deal enough damage to destroy the epidermis (I'm literally pulling this out of my backside at this point <img src="https://cdn.jsdelivr.net/joypixels/assets/8.0/png/unicode/64/1f61b.png" class="smilie smilie--emoji" loading="lazy" width="64" height="64" alt=":p" title="Stick out tongue    :p"  data-smilie="7"data-shortname=":p" />).  If we assume that an AHB in D&D terms, represented by a single-HD humanoid with a 10 Con, would be 14.5 pts from full-health to death.  That is going to be best approximated by taking a fireball to the face with no save from a 5th level caster (average damage: 17.5).Let us stick with BTUs and assume that dealing third-degree burns on our nude humanoid across 100% of the body = death (which has been the case almost universally until the creation of Burn Wards, and is only mildly improved today).  Let us say our average humanoid is a male of average height, body fat, and skin weight.  <a href="http://faculty.washington.edu/chudler/ffacts.html" target="_blank">7 lbs</a> (3.17 kg) is as good a measure as any for the weight of the epidermis in our Everyman, and 2-4% body fat on a US average 190 lb (86.63 kg) human comes to a 3% average of 2.59 kg.  Altogether we have 5.76 KG of mass to convert into a sticky goo.I am not going to convert Fat and Skin to their specific Caloric amounts.  A kilo of fat (which will have a higher caloric burn than the skin) come to 7700 calories.  44352 calories or 175 and change BTUs worth of energy in the flesh itself if we were to burn it <img src="https://cdn.jsdelivr.net/joypixels/assets/8.0/png/unicode/64/1f61b.png" class="smilie smilie--emoji" loading="lazy" width="64" height="64" alt=":-p" title="Stick out tongue    :-p"  data-smilie="7"data-shortname=":-p" />.Now we need to figure out the Specific Heat of this mixture. While not perfect, we know the <a href="http://www.engineeringtoolbox.com/specific-heat-capacity-food-d_295.html" target="_blank">Specific Heat of Lard</a> in KJ/KG/C to be 2.26.  1 KJ is .947 BTU, so I'm going to keep the number as is as we are doing WAGing here <img src="https://cdn.jsdelivr.net/joypixels/assets/8.0/png/unicode/64/1f642.png" class="smilie smilie--emoji" loading="lazy" width="64" height="64" alt=":)" title="Smile    :)"  data-smilie="1"data-shortname=":)" />.Our average temp is 35C off our desired base crispy-critter temp to leave a pile of skinless beings who are fried to muscle.  So 2.26 * 5.98 * 35 to get our baseline for fried humans.473 BTU for a flash burn to burn a pile of unattended flesh.  To be safe (considering air, radiant insulation from the rest of the body, etc) I would bump this up by around 100* at minimum. 47300 BTU to flash-fry a human.Honestly, I think it would be way higher than this simply because of surface area, but I don't feel like doing complex math... I like winging it <img src="https://cdn.jsdelivr.net/joypixels/assets/8.0/png/unicode/64/1f609.png" class="smilie smilie--emoji" loading="lazy" width="64" height="64" alt=";)" title="Wink    ;)"  data-smilie="2"data-shortname=";)" />.----Of course there are so many effects.  But that seems like a working system... The cost of casting a fireball with this system would be somewhere around 420 GP/'round'.  This is slightly more expensive than a Scroll of Fireball, but would not require that pesky Mage to be attached to the spell.420 / 17.5 - 24 GP/HP of average damage/area effect. 1.6667 energy units expended.  Means each use of your 'death ray' (I would figure it at a 10d6 to 20d6 power, or 35-70 damage) costs 840-1680 GP to fire.  This puts it at worse than a scroll of cone of cold on the low end, to cheaper than a Chain Lightning on the other end.For your 'dragon gates' to be a more permanent effect let's multiply that by 10x.  8400-16800.  By this reckoning it is cheaper (and more effective) than a permanent Wall of Fire with Permanency even at its highest level of effective casting for your low-end ability, and much more effective (if more expensive by 6k) than a permanent WoF on the high end.tl;dr: Overall I feel that, for magic effects, 1 2/3 EU/HP damage in a 20' span would be fair and fit the unit well.Slainte,-LoonookEDIT: This takes Fireball as the spin-off, and assumes a radius/cone of effect that extends at least the range of the fireball.  For spells such as Burning Hands (as an example) which require lower output for smaller area of effect?  Look to reduce the overall cost to bring it more in line with the figures... But really, why are you expending this ability for anything but mass carnage? <img src="https://cdn.jsdelivr.net/joypixels/assets/8.0/png/unicode/64/1f600.png" class="smilie smilie--emoji" loading="lazy" width="64" height="64" alt=":D" title="Big grin    :D"  data-smilie="8"data-shortname=":D" />.</blockquote>

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