Dryya

Drya was one of the Pale King's Great Knights chosen to protect Hallownest. She was presumably the chief protector of the Queen's Gardens. Her corpse can be found outside the structure where the White Lady lives, which heavily implies she died fighting against the Mantis Traitors (which the corpses of lie in front of her) to protect her.

Trivia

 * In a kickstarter update, Drya was meant to be a boss.