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"Extreme Encounters" is a musical piece composed by Yoko Shimomura that is used in Kingdom Hearts Birth by Sleep. It serves primarily as a boss battle theme.
"Extreme Encounters" is approximately two minutes and forty-four seconds long. The instrumentation includes: a string ensemble- violins, cellos, and stringed bass, flutes, low brass, snare drum, suspended cymbal, timpani, and piano.
The lively and variety of parts and tones found throughout this piece creates a unique combination of emotions. An ominous mood is felt due to the constant underlying lower pitched drones played by the low brass and stringed instruments. Likewise, an intense atmosphere can also be felt due to the accompanying and persistent rhythmic accents played by the timpani and other percussive instruments. Adding to this pressured environment are independent ostinatos played by piano, violins, and then flutes throughout the piece, creating a sense of urgency. The melody follows a repeated rhythmic figure that is initially heard in the mid-string voices, with a group of woodwinds- primarily, flutes- later borrowing this same melody.