Famitsu has a few more details about Shin Megami Tensei IV like a new character called the Black Samurai. The article says the Black Samurai is a mysterious character dressed in black armor.

If you played Shin Megami Tensei: Strange Journey you probably recognize the outfit – it’s a black Demonica suit. Perhaps, there is a connection between Strange Journey and Shin Megami Tensei IV?

Atsuko Tanaka who was Ultimecia in Dissidia: Final Fantasy voices the Black Samurai. Tayama (Houchu Ohtsuka) and Kaga (Kaoru Sasajima) were also introduced in the article, but details about those characters have not been released online.