DE, PL, CZ, SK, HU

It does not run through Prague. It runs through Poland and then crosses CZ from Ostrava to Břeclav. Then SK (Kúty, Bratislava, Štúrovo) and then HU.

Actually in central Europe the night trains usually join and split at some stations, so in Ostrava two trains join: from Berlin and from Warsaw. Then in Břeclav they split again (two halves from each half), one goes to Vienna, another to Budapest. So at the beginning there are two parts on each train and you have to choose the right one. But since the places have to be reserved, you cannot get on the wrong half.

Western Europe too: in Hannover there used to be a great switcheroo between the coaches to and from Amsterdam, Copenhagen, Warsaw/Prague (split in Berlin), and Basel. The currently suspended night train to Lisbon also split into parts to Madrid and the French border halfway.

Where did the lisbon train go? Final destination?

Why is it suspended?

As I wrote, one part to Madrid, the other to Irún at the French border. Initially suspended because of corona, but RENFE said they're not coming back; I don't know why.

I think it's Austria. As far as I remember the train Berlin <> Budapest passes through Vienna.

(I'm surprised, though, that the train would pass through five countries. AFAIK it doesn't pass through the Czech Republic.)

No. Before 1989 the train connecting Berlin-Prague-Bratislava-Budapest would not cross the iron curtain.

The only thing that changed a few years ago is Prague. Changed for SW Poland.

While there are multiple routes, I believe this one you're talking about has to go through Prague.

Poland?