Sariel and Abyss Sariel have been implemented in Japan servers. They use staff + cube as weapons. See 8/19アップデート情報 for details.
Sariel can be recruited after completing Armonia Episode 1 scenario. Abyss Sariel Card is available in 偽りの司祭 第2章 event mission roulette, as well as Imperial Wheel G 119 during 20-24/8, 2015.
Sariel and Abyss Sariel are voiced by Kaji Yūki (梶 裕貴), who performed in Attack On Titan (Eren Yeager), Accel World (Arita Haruyuki), Arslan Senki (Silver Mask), Guilty Crown (Ouma Shu), High School DxD (Hyoudou Issei), and Magi (Ali Baba).
Korean server has released Sariel & Abyss Sariel Preview . The latter is likely to be released in Lyndon Box.