[2] In 2013, Horowitz created the score for the Scottish short film The Groundsman, starring David O'Hara.
Horowitz's score blended themes from Mozart, Rossini, and Giuseppe Verdi with his original compositions.
[5] In 2020, Horowitz accompanied the harpist Heidi Krutzen for a performance of Alexander Scriabin's Etude.
[3] Horowitz's score incorporated some motifs from John Williams' original Harry Potter score with subdued whimsical pieces that accompanied the player's journey around the role-playing video game's open world.
[7] His works The Room of Hidden Things[8] and A Focused Mind[9] appear on the Hogwarts Legacy album Study Themes from the Original Video Game Soundtrack.