One of the special event weapons in the Japanese version of the game is a hammer called "Crazy D" that can heal your allies when used against them.

This is a special weapon designed in collaboration with Hirohiko Araki, the author of the manga "Jojo's Bizarre Adventure", and is a direct reference to Part 4's main protagonist, Josuke Higashikata, who possessed a Stand called "Crazy Diamond" that had great physical strength and speed, as well as the ability to heal people's injuries and repair broken objects.

The Client "Wounded Hunter" in the six-star ranking quest "Avenge the Fallen Hunter" says in the details of the quest: "My weapon... bounced off it's hide like a toy. That thing moved... so fast. Before I knew it... I was knocked cold. The Medicine Man says it's... just a scratch, but the pain! Avenge my flesh wound!" This seems to be a refrence to the Black Knight from the movie Monty Python and the Holy Grail, where the Knight proceeds to fight King Arthur and gets all of his limbs cut off, saying the lines: "'Tis but a scratch," and "Just a flesh wound."