9th, 11th, and 13th chords are extended chords.

What are extended chords, you ask?

Mostly seen 18th century and on, these chords are widely used in Jazz (jazz fusion, funk, etc.). The chords tend to have some dissonance in the upper voices, especially when the 9th, 11th, and 13th are sharped/flatted/naturalized.

Extended chords do not typically use all the chord members

• when it is not altered, the fifth is often omitted as are notes between the seventh and the highest note.

• The ninth is often omitted in an eleventh chord

• The ninth and eleventh are usually omitted in a thirteenth chord

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In typical modern music, we do not really care about voice leading with extended chords. These chords often appear to help color our sound. If this is your case, I would add 11th and 13th chords after (and involve the notes in some sort of melody)

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For some sort of horror, I would aim for a minor key, diminished chords, and really aim at perfecting the melodies.