I've been playing around with this for a while now, and I am beginning to think I am barking up the wrong tree.  I began by trying to make a variant of a mount buff, however, instead of applying a combat modifier each round of combat, I am trying to code the buff to add a number of hit points to the character per round of combat, based on a percentage of the damage that character does.

For the literature fans, I am trying to code a special encounter/item set:  STORMBRINGER and MOURNBLADE (from the Elric Saga).  For those unfamiliar with them, they are essentially vampiric swords that suck the soul from an enemy and give it to the wielder (along with a few drawbacks).  

At the moment, the best way I can think of to code it is by assembling the module and having the weapon apply a permanent buff (much like the mount) that applies a certain percentage of the damage a character does to the players HP.  I have the basis of the module written, and I have the basic code to apply the weapon name, but the buff is beating me.........

Any thoughts would be greatly appreciated.

How cool is that?  There is already a buff made........

Sichae you rock!  Thanks very much.