Deciding the best in a genre that's composed of bands that willingly and encouragingly rip other bands off, to the point where they might as well have been made by the same people, is a little like throwing darts at the wall. But instead of a board, there's a bunch of photos of delicious food you can then eat. No real right answer, whatever you land on you'll probably be pretty happy with, and eventually you have to take a step back and stop playing because you're stuffed. In a genre with such little variety and limiting rules, whatever is the best to you is probably more suited to your very specific tastes than anything the musicians can really do, and the difference is probably the small things that jump out to you and hook you where other bands doing the same thing would not. As such, with that preamble, I can pretty confidently say that this is definitely one of, if not the, best grindcore records of the past decade or so to these ears, and most of the reasons were surprisingly complex.
Well... Complex as far as grind can be, anyway. On a primal level, the primal adrenaline rush inherent in all grindcore, Mental Hygiene does absolutely everything right, with flying colors, and still does absolutely nothing outside the realm of tried and true grindcore to try and reel in new listeners. It has the blazing speed, catchy riffs and the powerfully gutteral vocals. Its take on grindcore is primarily informed by west coast cult legends Excruciating Terror, a crusty, more dependent on d-beat than average style emphasizing the sense of galloping momentum. You could totally point out differences between the bands (however minute and trivial), but Internal Rot is best summarized as an evolution of that sound, and even, arguably, an improvement; It is fully modern, absorbing the more slick sound of today's grind (compared to the more garage-y/DIY sound of ExTx) with the extra burst of speed and light usage of pyrotechnics to breath new life into its formula. The record's tricks are shown off quick, yet the band always knows exactly when to take a step back and let a crushing breakdown halt the blisteringly fast blasts (particularly fast - this is genuinely one of the fastest set of blasts I've ever heard), supported by some exceptionally gnarly, huge sounding drums - easily one of the best things about the record; A d-beat section (which are consistently catchy; Lashed with Viscera will probably be stuck in your head for sometime); bringing out its precious few shrieks to contrast the growls, or even tiny things like a little pinch harmonic or bell. At every moment, Internal Rot sound almost in a collective trance, playing everything and moving through each sections with surgical precision and complete coordination yet the record manages to feel immensely raw and on the brink of collapse. That's in in great part by, again, these phenomenal sounding drums; like bricks hitting the floor from miles above, and with cymbals so powerfully ringy they sound like bells from hell itself, and with much they are used and how highly mixed they are, their presence adds a suitably apocalyptic undercurrent that makes the album experience all the more gripping from start to finish, but add enough punch by themselves that even just one of these short songs can still leave you plenty breathless.
More so than most of their peers, Internal Rot feel like they craft songs, not just blasts and rows of 0s that only work when surrounded by other identical blasts and rows of 0s. No one will confuse these compositions for progressive rock epics, but remembering to make almost each and every track a stand out of its own is one of grind's best hidden keys to success which many, many struggle to get a hold of, yet IR feel like they're in full control of it. These are the main ways that Mental Hygiene stands out - Unseasoned listeners might come out hearing nothing but the same amorphous blob of dissonance they can get in any other album, but avid fans like myself will appreciate the light touches the record constantly adds to keep the listen engaging. There's no breathing room yet adding any feels like it would've only weighted them down, only distract from the point which is to assault the listener with pure grind. This type of directness is a dime a dozen, but few feel like they truly have no time for bull*** quite as much as Internal Rot does here. And fittingly, the band conclude the record with a hidden track covering their previous torch carriers Excruciating Terror themselves, adding even more speed and viscera to an already powerful song, as if to firmly exclaim: This is our sound now. And by the time it's done, you'll believe it.
Highly recommend, and my personal pick for best grind album of the 2010's.