Dungeons & Dragons is set to introduce a new feature for elves that will allow characters to change their gender once per day.

Every week, the D&D Beyond app releases new videos that explore the world of Dungeons & Dragons. Their most recent video features D&D lead rules designer Jeremy Crawford talk about the drow, one of the more popular elf subraces in the game. While the bulk of Crawford's video discusses drow culture, he notes that the upcoming Mordenkainen's Tome of Foes introduces a special ability that some elves use to choose their gender at the start of each day.

One of the big themes in Mordenkainen's Tome of Foes is the concept that elves were once a mutable race. Their creator Corellon Larethian was an androgynous being and elves could originally change their forms at will, although they eventually lost this ability when they descended into the Material Plane.

However, according to Mordenkainen's Tome of Foes, some elves retain a blessing of Corellon. As part of this blessing, these elves can actually choose their biological sex whenever they finish a long rest. These elves can choose to be male, female, or "neither" based on their moods or feelings.

Dungeons & Dragons, at least the most recent Fifth Edition, has made it clear that players don't need to be "confined" by binary notions of gender. The game's Player's Handbook notes that some elves are androgynous in nature after Corellon's image, while noting that players can also choose to present their characters however they wish.

So what does the concept of fluidity have to do with the drow, which have long been depicted as the "evil" subrace of elves? The drow come from an extremely matriarchal gendered society and have widely rejected Corellon as their god. A drow that can change their gender is seen as an affront to drow culture, not only because it's a direct blessing from Corellon, but also because they can choose whether to be part of the ruling female class.

Drow with the ability to change their sex usually become inspirations to other elves, and often turn out to be the heroes and peacemakers that emerge from a race that’s generally viewed as not heroic.

The drow will be just one of the many races explored in Mordenkainen's Tome of Foes, which comes out on May 29th and costs $49.99.

Note: This article was updated to reflect that the elves could change their biological sex, not their gender as indicated in the title. We also clarified that the drop who could make these changes were not subjected to violence in drow culture.