The story goes that Thor's hammer was crafted with great care and magic. It was bestowed upon him by Odin as a symbol of his strength and responsibility. The hammer's creation was a significant event in the mythological tale.
Thor's hammer return in the comics happened when he overcame various obstacles, showed great strength of character, and reconnected with the powers that granted him the hammer in the first place. It was a complex and exciting storyline.
Saitama obtained his power through a rather unconventional way. He simply trained non-stop, doing mundane exercises like push-ups, sit-ups, and running. This extreme dedication transformed him into the powerful being he is now. It's a simple yet unique origin story.
Thor typically gets his hammer back by demonstrating his noble character and commitment to justice. Sometimes, it involves facing difficult trials and showing that he has learned from his past mistakes.
Thor's arm loss in the comics can occur due to multiple reasons. Sometimes it's the result of a magical curse or a confrontation with an extremely powerful villain. The details change across different comic arcs.