This isn't an introductory paragraph because there's literally nothing to say about the genre as of 2021 that hasn't been repeated at least thousand times with each analogy becoming even more tortured, abstract and insufferable. We get it, leads lines = jizz and that's hilarious the first five times. Maybe ten. Please move on to the next paragraph.
It's somewhere through the second spin of "Desecration of the Host: Madness Complete" that it becomes blindingly obvious that Charnel Grounds are merely playing a "deathened" version of math rock and it's fucking sick. The vibrant, lush guitar tone with those arpeggios and the twinkly lead work wouldn't be out of place on This Town Needs Guns album. The track seamlessly flows into "Soul Scavengers of the Abyss" which continues this trend but with just enough traditional metal riffs thrown in to keep you on your toes. The vocals are so deep buried in the mix the songs are basically instrumentals, only further strengthening the math rock hypothesis.
Unfortunately the EP closes out with "On a Cross of Ether" where they basically play modern-era Gorguts; it's competently executed and succinct but feels out of place and disappointing. A great entree and main course followed by a cupcake with no icing for dessert.
Origami Angel have proven you can marry math rock with Lightning Bolt-esque out-bursts, so why not just replace that with death metal? It seems inevitable so jump on the idea before it quickly becomes over-saturated and we're sick of it.