In the end, it depend on whether or not your level is inspired by the game OR whether you ripped off the game. If you ripped off something, that violate our rule number 4:
(Quoting the rules page)
Characters, settings, or other content taken from franchises should be described vaguely enough that it isn't a dead giveaway that it is from the other franchise. This is a very important rule. If the page is different enough, this is not required, but if it is still the same content, write credit in a "Meta note" at the top or bottom of the page.