Liddian made some videos of EBF4′s end-game content. I think he’s still the only one to do so. They might be worth checking out if you’re considering buying the expanded game, or if you need help with these parts.
Here’s the endless battle. I didn’t actually think it was possible to survive this long:
Here’s the Dark Player boss rush:
Here’s the Miniboss rush:
Anyone who is having problems with the ice block puzzle on Battle Mountain may want to check this one out: