Suwa Foughten Field is probably my favorite Final Boss theme from Touhou.

This is a perfect Stage 6 Lunatic run on Touhou 10 by bjwdestroyer

Touhou 10 Fuujinroku ~ Mountain of Faith Characters (Click the image for uber-size)
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Touhou 10 Fuujinroku ~ Mountain of Faith

Characters

(Click the image for uber-size)

Source: pixiv.net

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Source: pixiv.net

Toccata and Fugue + The Venerable Ancient Battlefield ?

Only epic win can happen.

Toccata and Fugue in Battlefield — Tatami Stugiwo

Toccata and Fugue originally composed by Bach

The Venerable Ancient Battlefield ~ Suwa Foughten Field originally composed by ZUN