In Hogwarts Legacy, you have the freedom to play as a "dark" wizard, but the game does not feature a traditional "morality" or "evil" system like those found in games like Fable or Star Wars: Knights of the Old Republic. You can choose to learn and use the three Unforgivable Curses—Crucio, Imperio, and Avada Kedavra—by following the side-quest line of the character Sebastian Sallow. Using these dark spells in combat does not change how the world or NPCs react to you, and there are no legal consequences or "detention" for using them within the gameplay loop. You can also choose "meaner" dialogue options, extort NPCs for rewards, or keep quest items for yourself. However, the main story remains largely the same regardless of your choices; you will still be the "hero" tasked with saving the wizarding world. While you can roleplay as a selfish or cruel student who embraces the Dark Arts, the game is designed to keep you on a path that fulfills the central narrative, meaning you cannot truly become a "Dark Lord" who takes over the castle or canonically joins the villains.