[Marttt]

Well here is some snippet:

Spoiler

PHP Code:

public void OnEntityCreated(int entity, const char[] classname)
{
    if (StrEqual(classname, "witch", false))
        SDKHook(entity, SDKHook_OnTakeDamage, OnTakeDamage);
}

public Action OnTakeDamage(int victim, int &attacker, int &inflictor, float &damage, int &damagetype)
{
        damage = damage * 0.5;
        return Plugin_Changed;
} 


This will kindly cut the damage to half.

Didn't test but may give you some direction.