Dying 3.75 Edition (3.5e Variant Rule)
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 Dying 3.75 Edition
Based on the methods of death and dying planned for 4e, this variant rule alters when a character is dead and when they are dying. The system accounts for healthy tougher characters maintaining some toughness in the negatives, as well as scaling with levels. As I believe the 4e version is too much, this one is a happy medium between the two values of -10, and the large values in 4e.
 When do I die?
Dying is now a function of HD and your Con modifier. Specifially, your range which you are simply dying and negative is the normal -10 - (1/2 your HD x Con modifier). By having a high Con score and high levels you can ensure that, while you may be out of the fight, as long as your allies win you have a chance. It makes death less risky at high levels when -10 provides no buffer between being alive and being dead. A DM may wish to make life restoring magics more rare in return, however. Dying, at minimum, is -10 regardless of what your Constitution or HD is.
- Level 1 character with Con 16. (1 x 3) = -13
- Level 1 character with Con 10. (1 x 0) = -10
- Level 5 character with Con 14. (2 x 2) = -14
- Level 10 character with Con 12. (5 x 1) = -15
- Level 10 character with Con 20. (5 x 5) = -35
- Level 20 character with Con 14. (10 x 2) = -30
- Level 20 character with Con 8. (10 x -1) = -10 is minimum
- Level 20 character with Con 30. (10 x 10) = -110 (but this is a pure Con build, it makes some sense)
Looks good, save that I would set the minimum to be 1, and then add 1 on per point of Con Modifier (example: Level 1 with Con 16 = (1 x (3 + 1)) = -14). This allows those with weaker Cons at high levels to still potentially be knocked unconcious instead of completely outright killed by big-damage effects (Level 20 character with Con 8 = (10 * (1 + 0)) = -20 = better chance of actually surviving a Maximized Fireball) while helping to prevent the Con stat from becoming THE most important ability score in the game.