Which is why I voted her to win. The Lady of Pain exists in a realm where belief can become reality. Logically, if enough people believe she can win, she will win.
Plus, she has an army of rebus-speaking floating guys who can just bum-rush the competition and build a city around them while she Mazes anyone giving them trouble.
The Lady of Pain doesn't even have stats. She's a force of nature that can keep even gods at bay. I think WotC should absolutely make this a combat encounter, as it will be an automatic and obligate TPK.
Demogorgon over Strahd FTW! Really, Demogorgon would probably win any competition in my book: toughest demon prince, most awesome heads, best baked goods...
Strahd had to get past Baba Yaga's Hut, and Demogorgon beat out Verminaard, but I came really close to putting up Demogorgon against Fewmaster Toede. Now that would've been fun to see!