The band consists of Brendan Canty on drums, Joe Lally on bass, and Anthony Pirog on the guitar. Canty and Lally were the rhythm section from legendary Washington post-hardcore band Fugazi. If I recall correctly, I previously saw Canty on drums with Bob Mould more than a decade ago.
In my notes, I described the music as psychedelic post-punk jazz. I loved Pirog's amazing guitar playing. and effects and loop manipulation. You'll also never see a more intense rhythm section than Canty and Lally.
The Messthetics were amazing. Give this band a listen and if you get the chance, take in their live show. It's was a highlight of Hillside 2018, without a doubt. Just incredible.