We just came off of her over New Years. The second night (Nassau stop) is formal (Captains night event), but things were changed around because of New Years (Eve was changed to formal, but on previous ships, they didnt change the schedule and NYE was whatever the normal dress code was that night). I think the other formal night was normally Wed or Thurs. Usually the first and last nights are casual since you might not have access to you luggage (we had until midnight to get ours out the door the last night). There was a decades theme night (70s 80s 90s thing) and a Caribbean theme night (usually after a day in port and I think it was St Thomas, but with the change I might be wrong). The other nights are smart casual. Dont miss the ice show as its good!