Final Exam Boss: A boss that requires most of (if not all)the abilities you've learned in the game so far for you to defeat it.
Straight: In order to defeat Evil Overlord Tom, Bob has to use everything he's learned from fighting Tom's generals.
Exaggerated: Not only does Bob use what he's learned from Tom's generals, he spontaneously learns new techniques in the middle of the fight, right before Tom switches to the form said ability is needed for.
Downplayed: Tom has multiple forms like any "good" final boss, but Bob only needs to use the first one and last two abilities he acquired prior; the rest aren't needed.
Justified: The whole situation is a Secret Test of Character, and Tom wants to make sure Bob has mastered all of the proper techniques so that Bob may one day take his place.
Inverted: The Boss fight is actually unwinnable, as Tom has the perfect counterattack for any and every of Bob's moves.
Subverted: Things seem to be shaping up to a Final Exam Boss, but every one of Tom's forms are easily dispatched by running up to him and whacking him with your magic sword.