During his response, Prof. Willowstar itches himself absentmindedly and occasionally coughs.
"Ah, a very good question, Forge. The answer is a common one to biology: redundancy. Indeed, it would be very simple to bleed out a creature if a central pipe burst. However, there isn't such a central pipe. In its place are a series of many smaller vessels woven around each other. A larger number of them must be compromised to achieve a similar effect. In short, no blood vessel carries enough fluid on its own to leak out the system. Perhaps if blood didn't clot, but the cytoskeletal element of the central support structure can rapidly polymerize and roughly seal a leak. In their case, the wound scabs over before blood clots. The initial scab isn't completely tight, so some blood loss still occurs, but it prevents a rapid depressurization."
"Another good question, Spindrift. And exactly what I'm here to teach. Unfortunately, there aren't any large sections of this support structure immediately accessible. If you're feeling particularly daring (or foolish), there are two locations closer to the surface than the rest. They are the nutrient exchange center and the primary excretory membrane. You see, lunar creatures lack a continuous digestive track like we have. Food enters the mouth and is digested in an open pit. Though comparable to a stomach, the design is actually far more primitive. After partial digestion, the "stomach" absorbs the nutrients by phagocytosis. The inner skin surrounds the food and inverts in, forming bubbles near the stomach. Cytoskeletal elements carry these vesicles to the vessels of the nutrient exchange center for dispersal throughout the body. More accessible is the primary excretory membrane. Old skin membrane, as well as other bodily debris and waste products migrate toward the rear end of the beast via the skeletal network. In a process known as exocytosis, the outer skin and this waste is ejected. To limit unnecessary tissue loss, the blood vessels are particularly concentrated in this area. For the trackers in the room, here's an easy way to know you're following a lunar creature: look for the waste. It will be coated with dead skin and mucus."
Prof. Willowstar concludes his response with a coughing fit. By this point, he has a couple of hives. He reaches into his desk and takes out a syringe and some unidentified cocktail. He injects himself with the medicine and looks around. He notices Spindrift's shifting clothing and flickering blade. He narrows his eyes. "Spindrift! I said no magic in this classroom. I know, I know, psionics, not magic. Arcane, divine, psionic - it matters not. They're all magic. And I'm allergic. There. I've said it. I didn't want to, but apparently I need to give the incentive. Like some other unfortunate elves, I've developed an allergy to all forms of magic. Receiving a simple healing spell could kill me outright. Even from this distance your mind blade makes me itch. Please, put it away."
Prof. Willowstar continues, quite likely lost in memory. "Such a sad story, really. A curse followed by a contagion. The druid objected to my methods - a "perversion of nature" he called them, and sought to destroy the village-mech I called home - "tainted by the hands of a necromancer," he said. The one-two shot must have primed my immune system. The healing afterward nearly killed me. Had I not been in need of emergency healing, the allergy would have been fully developed, and I certainly would have perished. A sad day it was. I had saved my home only to lose it. How could I stay? The very air made me itch, heavy as it was with the animating magic. And it was all the worse because I had also lost my profession and my quest. I trained as a wizard, and now magic is death to me. But I can share my experience. If I can't bring the fight to the lunar menace, I can help others to do it in my stead."
"Oh yes, Firebat. Well, I haven't yet figured out how to make them burn. It's a very tricky task, and the research delves into magical nature, which, as you now know, I can't study anymore. You see, all of us are elemental in nature. We are combinations of earth, fire, air, and water, tied together uniquely into one whole. Lunar creatures, too, are of elemental combinations. But different elements. Some sort of lunar analog. When we burn, the fire is released. Lunar creatures don't have fire to release. After eating us for so long, there's a tiny amount of fire now, but it's not intrinsic. What we need is to research what coaxes out their elements. Until then, just douse them in oil and then light 'em. If you have the patience and the stealth, petreat them with a source of fire. Food, injection, whatever. Just fill them with something of terrestrial origin, and there's more fire to release."
Prerequisite: Rage class feature, Favored Enemy (class feature or feat)
Benefit: The sight of your most hated foe drives you into a frenzy, and you strike out all the harder against the abominations and all who ally themselves with them.
When your favored enemy is within sight, you can enter a rage as an immediate action (including on your opponent's turn, as the Instantaneous Rage feat). Additionally, you add your favored enemy bonus to the STR and Will save bonuses from your rage.
I am Omnirahk, half-Rahkshi ("Omni") of the WotC forums. I consider "Psionics in DragonMech" (see my website) my greatest contribution to anything d20 so far. At least, it's my most successful topic.