Перед and затем : which cases are these?

Question

In this sentence: Перед обязанности затем удовольствия can you tell me in which cases are duty (dative, genitive, prepositional?) and pleasure (genitive? plural?)? can you help me? thanks

Answer 1

The sentence is incorrect even excluding cases of обязанности and удовольствия issue. And the answer depends on what do you really mean.
If the sentence supposed to be

"сначала обязанности, а потом удовольствия"

then it can be helpful to insert skipped verbs here:

"сначала [идут] обязанности, а затем [идут] удовольствия"

In this case, it's easier to see that the case is nominative.

Answer 2

The sentence sounds strange. Better would Сначала обязанности, затем удовольствия or Вперёд обязанности, потом удовольствия

When I think on cases it's difficult for me to distinguish (perhaps someone will correct me here). Both would be either Nominative or Accusative.

I should also mention the Russian sayings/proverbs, that suit better here and mean the same thing you'd like to express:

Сделал дело - гуляй смело and Делу время, потехе час

Answer 3

There seems to be the first letter missing in the beginning of the phrase.

The most natural form would be, putting the lexical compatability aside, Вперёд обязанности, затем - удовольствия.

The cases in each part of the phrase are nominative.