User blog comment:DinoKev/Just some thoughts/@comment-5280660-20120804184031/@comment-5182322-20120804233245

The Nurse S and S+ were released as leaderboard prizes from Water Brigade.

If you are asking if they will be in the next epic boss chest then I would say its very unlikely, because none of the other leaderboard S/S+ exclusives have been released in Epic boss chests. Only the Grim Reaper was released but was different because the S+ was not released to the general public. If I was to guess as to another new epic boss S card it would be an S version of Siamang Monkey, but who knows Gree is pretty random about stuff. It could be that there isn't one like this event.