First off, and this is not the purpose of this post so I won't dwell on it, many of these ads ask for too much and offer too little remuneration.
But what I will discuss is that these overachievers, whatever you call them, require proper care and feeding otherwise they'll be gone before you can blink.
Since these superstars and ninjas tend to be smart, they know their worth and are looking for growth and challenge. If you don't pay them well and don't have a culture and managers that support growth, don't even bother. And that means if your managers are afraid to be outshown by their staff or are micromanagers, they will drive the overachievers away.
Your culture should also be collaborative, open, allow everyone a voice, and let them get work done their own way. The overachievers by definition want to achieve—not play games—so if you tolerate politics and other negative grandstanding, don't bother either.
The flip side of having someone so competent on staff is that they expect a lot since they give a lot. Give them a chance to contribute and learn and they'll be happy to do what you ask and more. Stifle them with bureaucracy, pettiness, redundancy, or don't allow their input, and they will have no problem walking, despite all the time, money, and resources spent to find and onboard them.
Are you looking for overachievers? If so, can you handle them?