We are late to this. From a mini-album called S/T, this came out at the back end of 2013, but is well worth revisiting.
Ratka are a four-piece from São Paulo who specialise in echoing vocals, darkly swirling guitars, and spooky organs to create fuzzed-out soundscapes. Equal parts post-punk and incantation, and psych-hook laden as hell, this is something a bit special.
Get S/T from Ratka's bandcamp page.