posta o script do monstro que esta editando aqui pra gente ver onde esta errando.

<?xml version="1.0" encoding="UTF-8"?>

<monster name="Demon" nameDescription="a demon" race="blood" experience="25" speed="120" manacost="0">

<health now="9999999999999999999900000000" max="9999999999999999999900000000"/>

<look type="107" head="0" body="0" legs="0" feet="0" corpse="2940"/>

<targetchange interval="2000" chance="0"/>

<strategy attack="100" defense="0"/>

<flags>

<flag summonable="0"/>

<flag attackable="1"/>

<flag hostile="1"/>

<flag illusionable="0"/>

<flag convinceable="0"/>

<flag pushable="0"/>

<flag canpushitems="1"/>

<flag canpushcreatures="0"/>

<flag targetdistance="1"/>

<flag runonhealth="15"/>

</flags>

<attacks>

<attack name="melee" interval="20000000000" skill="10000005" attack="10000000000"/>

<attack name="physical" interval="1000" chance="13" range="7" radius="2" target="1" min="-15" max="-25">

<attribute key="shootEffect" value="fire"/>

<attribute key="areaEffect" value="firearea"/>

</attack>

<attack name="physical" interval="100000000" chance="10000003" length="80000" spread="0" min="-15" max="-25">

<attribute key="areaEffect" value="energy"/>

</attack>

</attacks>

<defenses armor="6" defense="8"/>

<immunities>

<immunity physical="0"/>

<immunity energy="0"/>

<immunity fire="0"/>

<immunity poison="0"/>

<immunity lifedrain="0"/>

<immunity paralyze="0"/>

<immunity outfit="1"/>

<immunity drunk="1"/>

<immunity invisible="1"/>

</immunities>

<voices interval="5000" chance="10">

<voice sentence="MUHAHAHAHA!" yell="1"/>

<voice sentence="I SMELL FEEEEEAAAR!" yell="1"/>

<voice sentence="CHAMEK ATH UTHUL ARAK!" yell="1"/>

<voice sentence="Your resistance is futile!"/>

<voice sentence="Your soul will be mine!" yell="1"/>

</voices>

<loot capacity="200">

<item id="2230" countmax="1" chance="12000"/>

<item id="2379" countmax="1" chance="18000"/>

</loot>

</monster>

Mano, você exagerou, quando chega em uma certa quantia de vida, ai pode não pegar.

Exemplo:

<health now="70000000000" max="70000000000"/>

Realmente é um número exaregarissimo de vida.

Vai diminuindo a vida e dando "/reload monster" no server, tentando criar o monstro "InGame"...

Aí vc tem uma noção de quanta vida pode por.

Dica: Tenta por 999k, é mais certo de funcionar.