The itinerary lasts 1day 1hrs 34min, and has 2 steps, and it will cost 80 euros minimum.

Paris - Vienna
The step from Paris to Vienna lasts 14hrs 53min. You'll travel in a night train from the company ÖBB.
On board, you'll have access to: Drinks and snacks.
You can find tickets from 80 euros.

Vienna - Cluj-Napoca
The step from Vienna to Cluj-Napoca lasts 10hrs 41min. You'll travel in a intercités.