Fyodor Dostoevsky vs. Ace

Fyodor Dostoevsky vs. Ace is a battle fought between Rats in the House of the Dead leader Fyodor Dostoevsky and Port Mafia executive Ace using a card game.

It happened at a room controlled by Ace located inside a ship.

Prologue
Fyodor was captured by the Port Mafia, specifically ordered by Ace. Currently being restrained, Mori, Kōyō, and Ace are having a conversation on handling Fyodor. Ace offers to handle Fyodor himself to which Mori allows him to do so. Ace frees Fyodor from his captivity and brings him to a room he controls, soon after offers him to join hands with him to take down Mori. However, Fyodor proposes on killing Ace instead which made the latter angry and gives the choice of letting him live if he is willing to put on the collar.

Battle
Ace returns to the room. Soon after, Fyodor proposes to have a contest being the conditions that if Fyodor loses, he'll happily put the collar however if he wins. he regains his freedom. Ace agrees to the conditions but with him deciding the rules of the game - each one of them take turns in drawing cards and guesses if the card is lower or higher than the previous one, guess the right and the current player draws another card, otherwise the roles gets switched, whoever has the most right cards win.

The two starts to play the game. Fyodor had a good start, guessing correctly the value of the cards. However, Ace still being confident that his correct guesses won't last - gambler himself being an advantage on knowing what cards left at the deck. The game continues with Fyodor leading and guessing every card right eventually finishing the deck and wins. Unable to accept what happened, Ace tries to contact his guards but failed to do so due to it being broken and the door won't open either.

Fyodor claims that his organization have taken control of the underground but Ace reveals that they are actually in a ship and not underground. Furthermore, Ace brags that he have learn about Fyodor's ability - to "encase" a person's consciousness in his head and tells that he have listened to his conversation at the room after leaving. Fyodor applauds him for his but tells that he is trained for this but this is not the case for Ace. Trying to escape from the Fyodor's consciousness and going back to reality, Ace grabs a lamp and hangs himself.

Aftermath
Fyodor successfully escapes the room and obtains the list of Port Mafia's ability users.

Manga and Anime Differences

 * In the manga, the intercom is located at the wall. However in the anime, it was on the table.
 * Ace only holds a single key when trying to open the door after losing to Fyodor. In the anime, he is holding a set of multiple keys.