It starts with applying, Then you have a chat with HR (first round)
After that you need to do a business case alone, and you have like 90 minutes to complete and make a powerpoint presentation. (second round)
If they like the powerpoint presentation, then they invite you to the third round which is actually presenting the powerpoint from the case study and ask you questions about the case + some extra about you.
After this you get invited to the last round, which was an in person two day assessment in their HQ in Liechtenstein. The first day is just getting to know people and a tour of the plant plus some extra activities. The second day you have all the assessments, about 4 different ones. An interview 30min, a live case study (similar to the one you did before), a group project (where they give you a task and you need to discuss and come to an agreement), and then a scenario situation, you are given a scenario (my case was conflict resolution) and then you have to talk with someone to try and resolve it.
After this they give you an offer on the spot.