Arachnomania (5e Disease)
From D&D Wiki
Arachnomania is extremely rare. It will appear in Driders and Drider Spawn, whereas they will spread it with their bite. When bitten, the target must make a DC 13 Constitution saving throw or become cursed. There are two types of curses. The first only affects humanoids while the second will only affect beasts and monstrosities large or smaller. Those affected by the first type will turn into a Arachnicid while those affected by type two will have the Arachnicid Beast Template applied to them. The type 2 transformation will have less of a physical effect due to the curse being mainly geared towards humanoids. The creature may have some specific alterations specified to a type of spider.
Stage 1 (1-2 hours after initial bite): You experience discomfort in your body, spreading from the bite. Your hair becomes white and doubles in length, and any body and facial hair disappears.
Stage 2 (5-8 hours after initial bite): You experience pain similar to throbbing in your feet and anus, and your skin begins to harden, as well as the Anal cavity beginning to central into one point. This causes pain similar to burning. Your vocal cords are distorted and mutated to produce a variety of clicking and hissing, presumably to communicate with other insects.
Stage 3 (12-18 hours after initial bite): Your skin becomes hardened completely, resembling that of a carapace. Your anus, after achieving centralization, bloats and lengthens into an abdomen not unlike a spider’s. This normally causes you to collapse due to the weight of said abdomen. In female humanoids, the size of the abdomen triples to fit reproduction areas. During this phase, you experience worse pain similar to rashes of the areas covered, and stretching of your anus.
State 4 (24-30 hours after initial bite): Your affected carapace takes on a coloration of the spider the initial bite came from. If the spider was a tarantula, or other arachnid with hairs on it’s body, the subject grows similar hairs. The abdomen is seen to have a variety of organ growth, beginning with Silk glands and ending with the Heart deconstructing and moving to the abdomen. In female humanoids, additional silk glands and accompanying organs are formed in the breasts, which does not cease the production of milk. Female humanoids also gain reproduction organs. Your eyes become completely black, and enlarge. Your vision is increased eightfold, with a doubled radius of normal vision.
Stage 5 (1.5-3 days after initial bite): Your legs slowly bend backward and shape into that of the legs of a spider, with your feet mutating into tarsal claws. An additional 6 growths from your pelvis protrude and quickly extend to the length of the now-transformed legs, with spacing similar to the spider. You also gain 2 extra sets of arms. Your canine teeth become hollow, and holes protrude into the jugular, which quickly mutates into venom glands, and suck said venom into your teeth. Venom glands match that of the spider, and have even higher amounts of the venom that causes Arachnomania inside. This causes immense pain in your legs, gums, throat, sides, and lower back. Behavioral changes include that of territory, but you still retain your personality and IQ, but will be much more aggressive and durable. Female humanoids become protective of spider-like creatures. Your size also becomes large.
Stage 6 (4-6 days after initial bite): Upon completing stage 5, and you begin to stimulate produce in the silk glands, and are able to protrude the accompanying silk of the spider you were bitten by from the your spinneret. Female humanoids can also now use reproduction organs. After full optimization of the silk-producing and reproductive organs, you will be taken over by primal instincts. You have completed your transformation into an Arachnicid.
Arachnomania does not seemed to be geared towards creatures other than humanoids. So when it effects other creatures, the effects are slightly different and will occur a little sooner.
Stage 1 (1-2 hours after initial bite): The creature discomfort in their body, spreading from the bite.
Stage 2 (4-6 hours after initial bite): The creature experiences extreme pain in their back and anus. The anus bloats and lengthens, becoming a spider's abdomen. This causes pain similar to burning. Tumorous growths swell from your forehead and erupt into six additional, completely black “eyes” in which they are able to utilize without harm. Their original eyes become completely black, and enlarge to that of the others. Their vision is increased by eightfold, with a doubled radius of normal vision. Their skin becomes hardened completely, resembling that of a carapace. The affected carapace takes on a coloration of the spider the initial bite came from. If the spider was a tarantula, or other arachnid with hairs on it’s body, the subject grows similar hairs. The anus will bloat and lengthen, but not to lengths caused by Type 1. The abdomen is seen to have a variety of organ growth, beginning with Silk glands and ending with the Heart deconstructing and moving to the abdomen. Their vocal cords are distorted and mutated to produce a variety of clicking and hissing, presumably to communicate with other insects.
Stage 3 (7-10 hours after initial bite): 8 growths will emerge from the creatures spine and will grow into large spider-like legs. The teeth will become hollow and fill with a strong and potent venom. The creature has completed their transformation into an Arachnicid Beast.
Arachnomania can be cured with lesser restoration. Once transformation is complete, the creature can only be returned to normal through greater restoration. But if lesser restoration is cast after the transformation is complete, the creature may regain its former identity for 1d6 hours before reverting back to its primal form.