The Principal of The Academy is the one in charge of it, who can only with the greatest effort be overridden by the Academy Board. Their position is a heavy one, because they must juggle politics and keep the various countries satisfied, while also protecting the students. This leads to the uncomfortable situation where the Principal has to tolerate some forms of bullying. The Academy only holds its influence as long as enough countries acknowledge it and send their nobles. As such, they cannot afford to punish every transgression of students and teachers. They also cannot just leave out nobles as teachers, for the same reasons. Instead, these noble teachers are often given position where they can do less harm. One detail about the Principal that is kept quiet, is their strength. On their homeground, supported by their staff, the Principal is powerful enough to take on an entire army of Tarot users. If at any point an actual threat to the Academy were to rise, the Principal must be capable of putting an end to that.
Official RequirementsTo be eligible to become Principal, a few formal requirements exist. The Principal must have been a Five-Year graduate. Students that left the Academy earlier, however, could be put through symbolic classes to qualify instead. As such, this qualification is nothing but a distraction, abusing the fact that many students will leave during their final two years. The Principal must not have been a teacher. However, Combat Instructors, Recruiters, and Arena Supervisors, all do not count as teachers. Again, this requirement is a distraction. The Principal must be able to properly summon a total of two hundred Blades, Staves, Pentacles and Cups at the same time, with any form of manifestation. This is a requirement of strength. Keyword is the word 'properly'. In other words, the Board can nitpick. The Board may choose to lower or raise this number if desired. The highest it has ever been is three hundred.
Unofficial RequirementsThe real requirements are kept a secret. In reality, the official ones are solely meant to distract and officially eliminate candidates that don't truly match the real ones. First of all, the Principal must not be politically aligned with any country. Noteworthy here is that politically opposed is perfectly fine. This is meant to guarantee the independence of the Academy. Second of all, the Principal must be willing to keep all of the Academy's secrets. All their hidden alliances, information gathered on students, true nature and intel of their Recruiters, and so on. Lastly, the Principal must be capable of murder, yet unwilling.
The Principal and the five Academy Board members evaluate candidates. Usually they pick these candidates themselves. A candidate is eliminated if they receive at least two counter-votes. If multiple candidates qualify, the tiebreakers are most positive votes, then least counter-votes. There is no additional tie-breaker, so on a full tie, the Board must convince each other and vote again. Only if the Principal dies or openly announces their plans to retire, are applications accepted. This is usually done every few generations, to make the countries believe they actually have a chance at sneaking in one of their agents. In reality, the secret requirements will eliminate these candidates, so the official ones will be manipulated to block them instead.
The Principal has the final responsibility for and say in Curriculum and Discipline. There are only two ways to overrule their decisions: An unanimous decision by the Academy Board against their decision, or dismissing the Principal. This means that the Principal can change a class's teacher, move students to other classes, give out detention and other punishments, fire teachers, and expel students. However, severe interference is rare due to politics. Light disciplinary measures exist to both punish bullies and not cause diplomatic problems. Heavier disciplinary measures are by the Principal's order, and only handed out very lightly. To fire a teacher or expel a student, is an extremely rare thing to do. An unofficial duty of the Principal is quite simple: They need to protect the Academy. This means that if any hostile force attacks the Academy, they need to supervise the Academy's defenses. Whether by leading others properly, or killing opponents themselves, they must make sure the Academy stays standing.
Grounds for Removal/Dismissal
The only way for the Principal to be dismissed, is by the Academy Board voting to do so. If more than one person opposes dismissal, the Principal stays. Abstaining or not being present, will count as voting for dismissal. This is a formal procedure which has never been necessary.