the beginning of the music even sounds like a time traveling theme. it really suites his character

Mushoku Tensei Episode 21 OST Dragon God Orsted vs Rudeus Theme

Title: Ougon no Ken

Artist: Katou Tatsuya

Album: Campione! Matsurowanu Kamigami to Kamigoroshi no Maou OST CD1 


Campione! OST - Ougon no Ken (Golden Sword)

SAO Alicization Original Soundtrack Vol 3

a desperate battle, no way back

Composer: Yuki Kajiura

Magi Original Soundtrack ~Up to the volume of Balbad~ by Sagisu Shirou