Thread:Yorky97/@comment-25301601-20131125194509/@comment-7697305-20131125220059

That's added via a template – specifically, the Mario Smash template. As to how it works and how to implement it on another wiki...well, that's significantly more complicated, as it looks like it is dependent on the Navbox template, which was clearly designed by someone knowledgeable in MediaWiki coding. I could take a crack at it if you'd like, though I can't really promise anything (I'm really just learning when it comes to the more technical stuff).

Which wiki were you looking to add it to, anyway?