As with the lyrics for ~kyo~, I have trouble making sense what some of the lines are trying to say.
I just translate them as I understand them. :-)
混在, in all of the examples I found in dictionaries this word is only used as a suru-verb.
Fly away underground??
嘆く風の声 弾け飛ぶ 明日への誓いよ
Not sure how to interpret the word 弾け飛ぶ in the middle.
This is the imperative of arrive/reach. e.g. "Reach your destination!"
I'm not sure how to translate it understandably (with one word). I've put it as "fulfill." I'll probably change it if/when I can think of something better.
脱ぎ捨てちまおうぜ - Let's cast it off
Not sure what is being cast off.
In "Kiri no mukou de" there is a line "奮える魂", pronounced the same but written with a different kanji...
明日を射て - shoot tomorrow
Not sure what this means either.