User blog comment:Xilinoc/Ch. 564 (Mask is too fabulous to live)/@comment-823339-20140115133753

Renji's Bankai seems to have two parts, Hihiou (Baboon King) and Orochiou (Serpent King) and together they make Souou Zabimaru (Twin Kings Zabimaru). Previously Renji had only been using Hihiou, now he can use them both.