Your Best Nightmare

"Your Best Nightmare" is the 79th track in the Undertale Soundtrack. It plays during the fight against Photoshop Flowey at the end of the Neutral Route.

The song itself is composed of various parts. The first part consists of a very dark tune using the melody of "You Idiot," which plays only at the start of the battle; it is not included in the loop. Shortly after this, a heavily distorted version of Flowey's laugh plays. The song then alternates between two parts: variations on the first tune with a breakcore beat representing Flowey, followed by the sound of static from a TV and variations of "Your Best Friend" symbolizing the six human souls.

Trivia

 * The song is split into multiple tracks that play during the battle against Photoshop Flowey, all beginning with "mus_f_", except for Photoshop Flowey's laugh, the static noise and the ending section in the third and sixth stages.
 * Your Best Nightmare begins with "mus_f_intro", "bosslaugh", then repeats "mus_f_part1" and "mus_f_part2" until the "mus_f_alarm" sound effect is heard.
 * The six souls are filed as "mus_f_6s_1" through "mus_f_6s_6".
 * Another part, "mus_f_part3", is unused, however, some segments of it are heard during the third and sixth stages.[[File:Mus f part3.ogg]]
 * This is the fourth longest track in the Undertale Soundtrack, next to "Bring It In, Guys!", "Reunited", and "Undertale".
 * This has a steady BPM of 190, the same as Finale.
 * Almost all of the parts sample the Amen break, a drum break often used in rap music.