Plague of Thorns, Variant (5e Disease)
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Plague of Thorns
This disease is often found in torture chambers, should you cut yourself on a rusty blade (It's either this or tetanus). When you cut yourself on an infected instrument, make a Constitution check with a DC of 13. Should you fail, you contract the disease.
Stage 1: You begin growing thorns out your body. These are painful and make it impossible to wear plate armor. However, they increase your unarmed damage by 1 die grade (1 -> 1d4 -> 1d6, etc...). Every day, you must make a Constitution check with a DC of 13. Should you fail, you progress to stage 2. If you succeed three times in a row, the disease wears off and the spikes shed on their own after a few hours.
Stage 2: At this point, some of the thorns grow significantly larger, especially on the shoulders and the palm of the hand. The hand thorns each count as a shortsword, wielded in the off and main hand, but make it impossible to hold anything else. Each day you may make a Constitution check with a DC of 13; succeed three times (concurrently or not), and the disease progresses to Stage 3. If you score a critical hit with the Thorn Blades, the target must make a constitution roll or contract the Plague of Thorns themselves.
Stage 3: At this point, the disease begins to wear off. It is functionally identical to Stage 1, but the disease wears off fully after making one successful Constitution check with a DC of 13. You roll each day, as usual.