Passive Skills Too Weird? I Have No Choice but to Fish!

Leon heard the news that another person had sneaked into the Demon King's City. He sighed: Why do I get <temporary amnesia> when I hide my identity? This makes it impossible for me to even try to sneak in! And what is the power that memory transforms into... Who is the demon king who occupied the kingdom and made it his main city... What is hidden behind all the anomalies... After the fog is lifted... Lyon faces far more difficulties than destroying the Demon King and taking back the city.