Walking dead should be a gift not a curse

[Esp]

what about if the healer doesn't got the DRK healed up in time the DRK sacrifices all his mana (he needs to have at least 50% of his max-MP to acivate this) and gets a debuff wich reduces his max-MP to 0 for a short period of time on top of that? - but he survives

This right here is what I was thinking of, these exact lines. Should you enter walking dead and aren't healed to full, your current MP pool is simply converted to you HP and you enter a state where you can't regen Mana for a few seconds, like a pacify but it's effect on MP regeneration instead (from ALL forms, even your own)

The 50% requirement isn't needed either, since this pretty much puts DRK into its own "danger state" only this time, death isn't the only alternative.