Marvel: Starting with mastering the Dark Book

In Kamar-Taj, wielding the Dark Tome, a true sorcerer. Awakened with the Eye of Truth and the Immaculate Body, he can swiftly master any magic and reach incredible heights, without fear of any magical backlash.
Although he studied dark magic, Jiang Yu insisted that he was a legitimate mage! He only dreamt occasionally and hadn't done anything wrong. What dark magic? It was legitimate magic.
Jiang Yu: I am a respectful, kind, and gentlemanly mage who has no interest in power.
Gu Yi: Your respect for teachers and the Way means that even though I don't want you to learn, you insist on learning?
Strange: You have been very kind to me, except for the fact that you used magic to manipulate me, tricked me out of the Eye of Agamotto, and caused me trouble by dreaming recklessly.
Wanda: So the latest form of sorcerer gentlemanly conduct is to aggressively advance? And also to seduce other women and provide them with sleep aids?
Thanos: The Infinity Stones are mine, mine! You said you had no desire for power, so why are you trying to take the Infinity Stones from me?