Basically what the other two guys said, to reach legend status, you would have to do something that would be worth noticing, pioneer a new age / mod, etc.
If you're talking about becoming a Legend with a colored username, read through this.
In case you're talking about the Legend achievement, many of the achievements are broken or based on outdated circumstances, so I wouldn't depend on them.
Last edited by firebolty; Dec 20, 2015 at 11:43 PM.
you need to make an impact on the community for something like editing, replay making etc have a look here and see what the past and present legends got list