Castle Bleck Entry (せまりくる暗黒の空と... With the Sky of Impending Darkness...?) is a location that appears in Super Paper Mario. This the first area of Castle Bleck and serves as the main setting for Chapter 8-1.
Chapter 8-1: The Impending Darkness
The heroes have made it into Castle Bleck to confront Count Bleck himself. Tippi mentions Count Bleck's real name, Blumire, but shakes it off. The heroes press on forward confronting the many threats of Castle Bleck Entry including Koopatrols. They make it to a room with O'Chunks in it. O'Chunks is certain he is able to take out the heroes this time, but Bowser steps forward saying they have beaten O'Chunks many times in the past. O'Chunks gets upset by this comment and Bowser says he will gladly fight him one-on-one telling Mario, Princess Peach, and Luigi to move on forward. O'Chunks grows to a larger size and prepares to fight Bowser. After a long fight, Bowser defeats O'Chunks. However, the ceiling starts to fall but O'Chunks catches it saving everyone. Bowser asks why O'Chunks did that and O'Chunks replied saying that he was beaten and the heroes deserve to move on. Bowser also decides to help hold up the ceiling ordering the Mario Bros. and Peach to move forward. Bowser and O'Chunks then argue back and forth on who should leave but the ceiling soon falls down presumably killed them. The heroes said Bowser has survived worse than that and hit the Star Block at the end.