(Artemis Fowl) The Mesmer is one of the powers the fairies have. It requires direct eye contact and allows the fairy to control their target, plant post-hypnotic suggestions etc. For lore reasons, the fairies cannot use the Mesmer on each other, only on humans.
(Harry Potter) The Imperius Curse allows the user to subjugate the target to their will, controlling the target’s actions and thoughts. It’s been shown that people can resist the Imperius Curse, even to the point where they can’t be made to do anything.
Occlumency is an art based on defence of the mind. It helps you to identify foreign intrusions, and resist attempts to read your memories or implant suggestions.
Now considering what the Mesmer does, would it be effective on Occlumens or on people who can resist the Imperius Curse?
i think it makes sense for two kinds of legilimency—one where a wizard or witch is born with it, and the other learned. this is just my interpretation and theory, it is not necessarily canon.
Being Born With Legilimency:
Queenie Goldstein is the biggest example of a natural legilimens. She can hear thoughts of people around her effortlessly without really needing to try. It is rare to be a natural legilimens, and this form of legilimency is very powerful and strong. However, occulemency done properly can still block the legilimens.
Learned Legilimency:
Voldemort, Severus Snape, Albus Dumbledore, and, headcanoned, Gellert Grindelwald all learned Legilimency. How well the “mind-reading” works really depends on the wizard/witch. For example, a powerful wizard like Voldemort’s legilimency would be stronger than most other wizards’. Hearing thoughts can not be learned, no matter how skilled the person is. When using legilimency, one has to make an actual effort to do so, though the effort can be significantly reduced (once again with the example of Tom Riddle).
Occulemency:
Occulemency also depends on practice and skill of the person. A wizard/witch can not be born with this ability—all minds start out vulnerable. However, learning occulemency is much easier if the person is a legilimens, or vice versa. Canonically if someone has deep emotional hurt or pain they are more likely to master occulemency, like Severus Snape. Being able to accept your emotions and situation is also a big part of it, which is why Harry couldn’t do it (he was too arrogant).
I would think that most learned legilimens know occulemency: severus obviously, but albus, tom, and gellert too.
Can we just take a minute and think about how true this is? Harry, Ron, and Hermione were not the best choices to fight a Dark Lord. They were children. But not only that, stronger people with better opportunities came up in the stories and NO ONE noticed them. A man in the Leaky Cauldron (I believe) was doing WANDLESS magic while distracted. Narcissa Malfoy looked directly into the Dark Lord's eyes and told him that Harry was dead when she knew that he wasn't, and did. Not. Get. Caught. And Severus Snape managed to fool him into believing that he was always on the Dark Side. These people. They should be the golden trio.
