Design Diary 12

"Ugh, I don't feel so good…"

Poisons and diseases. If ever there were a "This is a really cool idea that utterly fails in practice" rule, these two would be near the top of the list. They work really well (almost TOO well) at low levels, but as Fort saves increase, they become increasingly less effective. Not only that, but they're boring: "Oh, make a Fort save. You failed? Okay, you take… *rolls* 3 points of Dex damage." Can you tell me if that's a poison or a disease, and if so, which one? I didn't think so. They all follow the exact same rules - immediate save or you're affected, and one minute later you make another save, ad nauseum until you die or recover. Boooring.

Awhile back, I rectified part of this problem with the Book of Plagues and Afflictions (yeah, it's a dorky name - sue me), which gave diseases new life - each disease had different effects, different stages (some worked faster than others), different cures, and different strengths (because some diseases simply have no cure at all). Unfortunately, it's a little too detailed for inclusion into the core rules, but I do plan to adapt it as an optional add-on.

Now, diseases have no set DC - the DC is really whatever you want it to be, except in certain rare cases like mummy rot. Poisons, OTOH, are based on the creature's Con score. But wait! Non-creature poisons don't have a set DC! In the real world, the most venomous creatures on earth weigh 5 pounds or less - the stonefish, the black mamba (okay, so it weighs 10-15 pounds, but its venom can kill you 20 times over), the blue-ring octopus, the sea snake, etc. The most poisonous vertebrate in the world, according to Wikipedia, is the golden dart frog, which is about 2 inches long and weighs under a pound; its poison can kill about 15,000 humans per gram, which is roughly 15 times as powerful as the black mamba, the most poisonous snake. Under the D&D rules, though, a black mamba would be considered a Medium viper, with a DC of 11. 11! A L1 commoner could shrug that off 45% of the time. So I decided to create a system whereby poison DCs are not dependent on HD - much like previous editions, and just like diseases. Here's a rough overview of what I've got.

Poisons are rated by their strength - Mild, Moderate, Strong, or Deadly, just like I did for diseases, plus Epic for gods/demon lords/etc. The DCs, onset times, and effects are based on strength. For example, a moderate snake venom would have a DC of 14-18, an onset time of 1d4+1 rounds, a check time of 1d6 minutes, and deal 3-6 points of ability damage on average (I've also got other effects, like sleep poison, sickness, paralysis, etc.)

Poisons also have a varying number of saves, based on their strength - Mild is 2, Moderate/Strong 3, and Deadly 4, but you don't have to make consecutive saves - any success is counted toward the total required. So, one person could get lucky and make his 3 saves vs. the moderate snake venom in an hour or two, while someone else could be taken to the brink of death before recovering. The way it works is that you have to make a number of successes before a set number of failures. So Mild is 2/5, Moderate is 3/6, Strong is 3/5, Deadly is 4/5, and Epic is 5/5.

I also came up with a set poison pricing system. I tried to reverse-engineer the prices from the DMG, and I couldn't come up with anything that covered all the bases - some poisons would follow the formula, and some wouldn't, but I've gotten close enough to make a workable set of guidelines.

Best of all, I don't have to tweak a whole lot - as it turns out, most monsters' poison DCs (and the damages) are dead on for their projected strength. I've had to adjust a few here and there, but nothing major.

So what does it look like? Here are a couple examples:

Bebelith poison: Injury; strong neurotoxin; DC 18, onset 1d3 rounds; check 4d8 rounds; initial effect 2d4 Con damage, secondary effect 2d6 Con damage.

Pseudodragon poison: Injury; moderate soporific; DC 12, onset 1d6 rounds; check 1d4 minutes; initial effect -2 to AC and attacks, secondary effect sleep 1d6 hours.

Obviously I haven't gotten to the normal poisons yet; I hashed this system out primarily so I could get back to work on the monsters. So far, it's turning out really well, so I'm happy.

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