Bom amigo então não se trata de drenar vida HP, más sim ganhar HP ao derrotar o monstro.
Geralmente os comandos para se montar um script de item podem ser encontrados no arquivo
rathena-master\doc\item_bonus ou dos próprios scripts já existentes no Item_db.
Os comandos para este item são estes.
HP/SP gain
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bonus bHPGainValue,n; Heals +n HP when killing an enemy with a melee-physical attack
bonus bSPGainValue,n; Heals +n SP when killing an enemy with a melee-physical attack
bonus2 bSPGainRace,r,n; Heals +n SP when killing an enemy of race r with a melee-physical attack
bonus bLongHPGainValue,n; Heals +n HP when killing an enemy with a range-physical attack
bonus bLongSPGainValue,n; Heals +n SP when killing an enemy with a range-physical attack
bonus bMagicHPGainValue,n; Heals +n HP when killing an enemy with a magical attack
bonus bMagicSPGainValue,n; Heals +n SP when killing an enemy with a magical attack
Segue abaixo o item já criado!
19163,Catherina_Von_Blood,Boneca da Succubus,4,0,,300,,0,,0,0xFFFFFFFF,63,2,256,,1,0,1527,{ bonus bHPGainValue,500; bonus bMagicHPGainValue,500; bonus bLongHPGainValue,500; bonus bSPGainValue,50; bonus bMagicSPGainValue,50; bonus bLongSPGainValue,50; },{},{heal -5000,-500;}
Vlw Flw!