4. Even The Master Was Impressed With Her
BBCThe Mark of the Rani had the titular villain team up with the Master since they both had reasons for wanting the Doctor out of the picture. Their villainous partnership wasn't really smooth sailing with two such powerful personalities wanting to be in charge, but despite their bickering, one thing was obvious. Although the Rani and the Master treated each other with ill-disguised contempt, there was also a hint of respect in the Master's interactions with her (a respect the Rani never really reciprocated). The Master considered himself a genius (which he was), but he recognised the same qualities in the Rani and respected her for that. On the other hand, the Rani was less than impressed with the Master. She found him slow and considered him incompetent, and she vehemently loathed their alliance. Still, the fact that the Master, an extremely impressive personage in his own right, found something to admire and respect about the Rani gives us a clue as to how intelligent and powerful she really is.