Or so perhaps the cursed belt of giant strength that converts its owner to the opposite sex (I forget the name of it)
I remember that belt. Don't remember what it is called, but I definitely remember the item.
Girdle of Masculinity/Feminity. Straight out of the 1e DMG for our 1e Module. Or OotS.
I amThat guard and I will be best friends soon

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.