Add a new rule, called “Hurt”. Place this rule in the ruleset so that it contains floor 56. If that is impossible, place this rule in the ruleset so that it contains floor 72. If that is also impossible, then something is broken. Place this rule wherever the enacting admin wants to. Its contents are as follows:

Add a new gamestate, called “hitpoints”. It can be a non-negative, real, number (for example: 0.001, pi, 69). Every (unidle) player has this gamestate. It defaults to 100. It is publicly tracked.