In the intervening years, Deacon had toured heavily and focused on other collaborative projects such as the 2017 ballet The Times Are Racing with New York City Ballet resident choreographer Justin Peck,[8] a 2019 performance with the Baltimore Symphony Orchestra,[9] and scoring feature films such as Theo Anthony's Rat Film[10] and Finlay Pretsell's Time Trial.

[12] In addition to finding new inspiration in these collaborative projects, during the recording of Mystic Familiar Deacon had begun regular practices of meditation and therapy, and began to use the Oblique Strategies cards created by Brian Eno and Peter Schmidt as creative prompts.

[13] Deacon has also cited David Lynch and his book Catching the Big Fish as an inspiration on the writing and recording of Mystic Familiar.

[14] A first video from the album, for the song "Sat by a Tree" starring Aparna Nancherla, was released October 29, 2019.

[16] In his review for AllMusic (in which its editorial staff rated the album 4 stars), Paul Simpson characterized Mystic Familiar as Deacon's return to "majestically arranged synth pop," characterizing its arrangements as "driving and full of excitement" and finding the album's lyrical themes of nature and inner peace "encouraging and empowering without relying on self-help clichés.