There's a visual novel called 'Fate's Twist' where a guy loses his arm due to a magical curse. The curse was cast by an evil sorcerer and has a significant impact on the character's journey and development throughout the story.
The way Oliver Queen loses his arm in comics isn't always the same. Sometimes it's a result of a risky mission gone wrong, or it could be from a confrontation with a villain with unique abilities. It all depends on the particular comic storyline.
Misty Knight loses her arm in a rather tragic incident. She gets caught in a dangerous confrontation where she underestimates the enemy's power and pays a heavy price.
In some fanfictions, Natsu might lose an arm in a powerful battle during the Grand Magic Games. Maybe he overestimates his strength while facing a super - strong enemy and in a moment of distraction or miscalculation, the enemy lands a fatal blow on his arm, severing it.
In this fanfiction, once Natsu loses his arm, the story progresses in several ways. At first, there's shock and sadness among his friends and the guild. Natsu has to come to terms with his new reality. He starts to train differently, focusing more on his magic control. There could be a sub - plot where an enemy tries to take advantage of his weakened state. But Natsu, with the help of his friends, overcomes these challenges. He may also meet some new characters who have knowledge about arm - restoration magic or something similar. As he embarks on this journey, the story could explore themes of perseverance, friendship, and the power of the human (or in this case, dragon - slayer) spirit.