The event is headlined by Ian McCall vs. Kyoji Horiguchi. You can read more about the lineup here, also for the Saitama Super Arena events RIZIN will be experimenting with "Season tickets" for that arena and you can read more about that here.
This event takes place May 6, and might be streamed on FITE TV like they did the New Years Eve show. I'm sure those details will come soon.