There are at least 3 types of adversarial teachers:
Type 1. The anti-role model. You encounter some asshole who is assholish in specific ways that you choose to precisely reverse.
Type 2. The guru of nothingness. You trek into the wilderness, complete a road of trials, climb the holy mountain, meditate for 5 years at the guru's feet in anticipation of the secret teaching, only to be informed at the end that the guru's secret teaching is that the guru has no teaching whatsoever.
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Type 3. The Phantom Tollbooth. This is a lot like the guru of nothingness, but you are denied access to the secret from the outset. Someone informs you that you are not worthy of hearing the secret, & only after you're done the road of trials and the impossible feats of strength -- only then do they inform you that the secret teaching teaches that what you've already done was impossible.