With Dangun Feveron now released on japanese PSN for PS4 M2 just announced that Ketsui: Kizuna Jigoku Tachi, CAVEs famed bullet hell shooter will be released in the same series. Though no platform was announced it seems logical to assume that this will be a japanese PSN download only game for PS4 just like Battle Garegga REV.2016 and Dangun Feveron.
To me this is one of CAVEs most brutal games. Punishingly difficult but lovely art design and a great soundtrack.