if (y > (obj_uborder.y - 10))
{
    if (off == 0)
        off = 1;
    else
        off = 0;
    if (green == 1)
        off = 2;
    bl = instance_create(x + 20, y + 10, obj_exhaustbullet);
    if (instance_exists(bl))
    {
        bl.dmg = dmg;
        bl.off = off;
    }
}
alarm[0] = 6;
if (green == 1)
    alarm[0] = 10;
if (pop > 1)
    alarm[0] *= 1.5;