From GameWatcher: “Bloodstained Ritual of the Night will, at one point, task you with getting through a Hidden Desert biome that’s part of the game’s humongous enchanted castle. This is one of the more challenging areas of the game, but here we’ll tell you what to expect and how to prepare.
Of course, Bloodstained Hidden Desert also comes with a special boss encounter that will push you to your limits. No one said the game would be easy!”
Source: N4G PC Bloodstained Ritual of the Night Hidden Desert Guide