The series of artists you mentioned——primarily collaborated on the 2022 album titled ЧЕРЕН ПЕТЪК (Black Friday). These artists are prominent figures in the Bulgarian trap and hip-hop scene, often associated with the Murda Boyz collective.
The "long piece" likely refers to one of their major collaborative tracks or the album itself, which features several high-energy songs with multiple contributors: bobo_armani_x_niki_kotich_x_pameca_x_kickdown_x...
: Another significant track from the same album featuring Bobo Armani, SST, Niki Kotich, Pameca, and Kickdown. bobo_armani_x_niki_kotich_x_pameca_x_kickdown_x...