Rivers of Heresy is the debut album by British duo Empire State Bastard, consisting of Simon Neil of Biffy Clyro and Mike Vennart of Oceansize, released on 1 September 2023 through Roadrunner Records.

remarked that the album "manages to surprise by bringing out lesser seen sides of its creators", as Vennart "has long showcased a songwriter of craftsmanship and nuance, so it's startling to hear him being so unremittingly brash here.

[5] Andrew Trendell of NME thought the album "too hard for most Biffy fans and not pure enough for many Slayer faithful, but it's its own wonderfully weird wee beast.

[8] The Line of Best Fit's Elliot Burr stated that "the mathy and shouty post-hardcore of Neil's early noughties output turns its intentionally ugly head once again on the aptly dubbed Rivers of Heresy", which "flourishes when it veers into heady atmospherics".

[6] Joe Goggins of The Skinny described it as "punishingly loud, often furiously paced, and has Neil vocally channeling Chino Moreno as he flits between screaming and singing.