Robert Dudley (ロバート・ダッドリー, Robaato Daddorii) is the frail-looking Vice-Chancellor of England's Oxford Academy and is ranked tenth in TRUMPS alongside William Cecil. She is also the owner of the Testamenta Arma Brachium Justitia Novum.
Her frail stature causes her to have a high blood pressure.
- Ability: "Repulsion" (“打ち払い”の術式, Uchiharai no Jutsushiki) - Robert Dudley summons a weapon that resembles a tennis racket to "swat away" incoming enemy attacks against her. Is effective against projectiles, but can also be used to send immobile objects flying.
- Testamenta Arma: Brachium Justitia Vetus (巨きなる正義・旧代, Ookinaru Seigi • Kyuudai, lit., "Gigantic Justice: Old Generation") - One of two Testamenta Arma that represent the virtue of Justice, the other owned by Francis Drake. This Testamenta Arma allows Robert to remotely control the movements of weapons near her. In conjunction with William Cecil's "Distribution" Ability, she can use the offensive might of an opposing army to destroy itself without resorting to direct offense. It seems, however, during her final confrontation with Malga Naruze, that Robert only needs the Arma to gain control of weapons and that she is capable of utilizing weapons already within her control through her mind alone.