Door Key

The Door Key is a Key item that can open the door in the ?????? floor in Card Castle, leading to Jevil's prison. The Door Key can be created by asking Malius to fix the three Broken Keys. However, Malius notes that the key holds a "terrible energy" and advises the party to never use it.
== Additional Uses ==
* When used, the Door Key creates a small door which admits the party to Jevil's cell.
== Trivia ==
* The Door Key is mistakenly called the Prison Key when it is fixed by Malius.
* In the modified version of Deltarune's Chapter 1 used in Undertale's 6th anniversary stream, the Door Key is instead found in the top-left corner of the ?????? floor, with a sprite not in the normal game. When picked up, it is described as being "caked in dog fur and frosting."
* The Door Key cannot be brought into Chapter 2. Even if it is in the inventory at the end of Chapter 1, it will disappear when the save data is loaded into Chapter 2.
== References ==
fr:Door Key
ru:Дверной ключ
zh:牢房的鑰匙