"[16] Manish Argawal of Mojo wrote, "Engine Of Hell sees the Californian singer-songwriter ditch her signature expansive arrangements for an eight-song set of piano-framed ballads that dig deep into youthful memories.

This newfound instrumental austerity can be forbidding at first, but repeated spins reveal lyrically acute portraits of grieving a family member during childhood (Body); a loved one battling addiction (Blooms Of Oblivion, cut with acoustic guitar and violin); and, less ominously, enjoying music with a friend (Dancing Man).

Rundle has written movingly on social media of struggling with pandemic enforced isolation, and the quietly majestic Return, with its poetic allusions to loss and loneliness, will resonate with many who have felt the same," and awarded the album 4 out of 5 stars.

The lyrics are wrought with dark meaning and somber emotion, and the lack of accompanying instruments makes their impact all the more poignant" and "Although the gear may have shifted down, the creative vision of Emma Ruth Rundle continues to moves onward.

"[15] James Christopher Monger of AllMusic claimed, "Rundle has tempered her sweeping post-rock cinematics with lyrical vulnerability in the past, but Engine of Hell is a braver and bolder beast, as it lays bare the soul of its creator and dares the listener to reckon with it," and awarded the album a 3.5 out of 5 stars.

"[9] Writing for Beats Per Minute, John Amen gave the album 78% and concluded, "While some of the instrumental interplays and gestalts of Rundle’s previous work are undeniably stunning, Engine of Hell underscores her gifts as a songwriter and for minimalistic arrangement, also illustrating her talent for unadorned performance.