When a character first encounters a vector, they must succeed in a DC 15 Fort save to avoid infection. While victims of lobsterficiation carry the disease, other vectors might include curses, magical creatures, or even tainted food and drink (such as water consumed after a rain of tiny dead monsters).
If a character is infected, each day after the first they must roll a DC 15 Fort save. Failure indicates a bodily change, which occurs in the order below:
1. Body grows shell-like carapace. +4 to AC, armor cannot be worn.
2. Left hand becomes pincer-like claw. 1d8 damage. Can transmit lobsterfication.
3. Body becomes hunched. Permanent loss of 1d4 Agility and 10' of speed.
4. Right hand becomes pincer-like claw. 1d8 damage. Most spellcasting is now impossible. Can transmit lobsterfication.
5. Body grows extra pair of legs and victim can no longer stand upright. Head is unchanged. Lobsterfication is complete.
The process of lobsterfication can be halted with a Lay on Hands check sufficient to do 3 HD or more of healing, but more powerful magic is needed to undo effects that have already taken place.
Average Lobsterman: Init -1; Atk claw +0 melee (1d8 + lobsterfication); AC 13; HD 1d4; MV 20’; Act 1d20; SP lobsetrfication (Fort DC 15 avoids); SV Fort +0, Ref -1, Will +0; AL N.