native UnitDamagePoint takes unit whichUnit, real delay, real radius, real x, real y, real amount, boolean attack, boolean ranged, attacktype attackType, damagetype damageType, weapontype weaponType returns boolean

//...
    local unit caster=GetTriggerUnit()
    local real delay=1.00
    local real radius=100.00
    local real x=0
    local real y=0
    local real amount=500
    local real 
    call UnitDamagePoint(caster, delay, radius,x,y, amount, true, false, ATTACK_TYPE_NORMAL, DAMAGE_TYPE_NORMAL, WEAPON_TYPE_WHOKNOWS)
//...