Mirror of the World is an interesting and slightly controversial song. The intro is just really long which makes it rarely reach the good parts by the time a normal game of Strive is over. But I don't care about that, because I rarely judge this series' music for its quality during gameplay. Also it relates to Delilah, which means it relates to Bedman, which is a good thing.
Melody
Nothing spectacular, but good. The beginning part in particular is very memorable.
Evolution
This is the reason a lot of people don't like this song. By the time the (very slow) intro is over, the first round of most matches is likely over. However, I am not taking in-battle context into consideration. I think it adds quite a lot to the song, as it feels like Baiken reflecting on her life. I also think the ending part is quite a good evolution of the song.
Emotion
Like most songs, the ending is emotional. But I think the beginning also has some emotion to it. Like I said in other places, it feels like a reflection of life.
Bangerness
Listen, I love that first section, but it isn't a "banger". The rest of the song is though!
Characterization
This song feels like all of Baiken's themes, but slower. Fittingly, this seems to represent her "reflecting" on her life through the "mirror of the world". Who or what this mirror is isn't explicitly stated, but I think Another Story's release pretty clearly put Delilah into that role.
Lyrics
An intersting choice to add lyrics in a different language. I will confess however that I do not know what they mean at all. Google translate won't help me. So I am not sure what they add to the meaning of the song. The rest of the lyrics are quite good though! I especially like the backing voice at the end.
B.O.F. Bonus
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Bread 
