timer--;
if (timer <= 0)
{
    var zobj = instance_create(x, y, obj_afterimage_grow);
    zobj.sprite_index = spr_spare_z;
    zobj.speed = 12;
    zobj.direction = zcounter * 40;
    zobj.friction = 1;
    timer = 2;
    zcounter++;
}
if (zcounter >= 9)
    instance_destroy();