Anna Komnene
Along with Tugorkan, Boniak, or Maniak, was one of the Cumans' "outstanding leaders", named by Anna Komnene, who came to assist the Byzantine Emperor Alexios I Komnenos against the Pechenegs. The united Byzantine and Cuman army annihilated the Pechenegs in the Battle of Levounion on 29 April 1091. Historian Florin Curta writes that the two Cuman chieftains plundered the eastern regions of the Kingdom of Hungary on their return to the Desht-i Kypchak, or Cuman steppes. Pletneva says that Boniak and Tugorkan together supported the pretender Pseudo-Diogenes against Emperor Alexios I in 1094, but Anna Komnene did not refer to Boniak's participation in the fights.