More HP possibilitys, how?

[STM1993]

I want to give a Char more Hp (>500) but i don´t know how.

Check the mainsite. Here's a link to one of the relevant articles you'd find useful.

My first idea was to let him spawn an invisible Heal balls on reaching "bleeding"-low hp
and controll his HP by abdonning the MP for him compleatly and regulate it over the amount of healing/mp cost.

There isn't a way to automatically detect your current HP level.

But MP is something that regenerates which would give hime Stupid amount of health (esspecialy while beeing on low MP)

There are ways to add/decrease MP for characters, but under data changing the things you can do for MP are limited, and MP regen rate is one of the limitations. MP regen is hardcoded into the game's lf2.exe file, you'd need to do HEX editting if you want to have perfect control over MP regen.

For most characters, the formula for MP recovery rate is:
(500-health)*0.01 + 1
^ Translation: Minimum 1mp per 1 tu(1/30 of 1s) regen rate. You regenerate +1mp/tu faster every 100hp you lose, up to a maximum of 5mp/tu. (500/1,400/2,300/3,200/4,100/5)
(500-health/2)*0.01 + 1
^ For Julian/Firzen (id: 52,51). You regen 3mp/tu at 500hp, 4mp/tu at 400hp, 5mp/tu at 200hp.