void main()
{
    /* only execute for PC's entering an area */
    if(!GetIsPC(GetEnteringObject())) {
        return; }
        object oCreature = GetEnteringObject();

   //Make sure the opener is a PC

    ApplyEffectToObject(DURATION_TYPE_TEMPORARY, EffectDarkness(), oCreature, 999999.0f);

    object oArea = GetArea(OBJECT_SELF);
     // place here the % chance of rest being interruped excample here 33% chance of rest being interuped
    SetLocalInt(oArea, "nMonChance",70);
     // place here the blueprint refrenfrence tag of the creature you wish to attack them
     // or place the word CUSTOM which will send a 201 event to the area starting your won script
     // here it is a goblin
    SetLocalString(oArea, "sMonster","nw_skeleton");
}