Well let's do the math. Metaknight said that Kirby needed 2,000 years of training to think on his own, fight, even speak. Metaknight is a pro at monster slaying. Soo, I say at least 5,000
I have read on a kirby right back at ya website it said that meta knight is 50,000 years old and that he could live forever. Oh btw I found this on a website months ago and it said what day meta knights birthday is and it is June 21st around the time of my birthday. So yeah I guess that answers the question and more.
