Well, even though Hungary and Zimbabwe had larger currency depreciation, I think the fact that neither ended with the Holocaust makes Germany's "worse"
Summarized from memory: At the end of the 1st world war, Germany was given a huge fine. The Deutsche Mark, deliberatly or not, devalued a lot. The large recession and poverty gave the opportunity for facism and the Nazi party to gain popularity. After the 2nd world war the allied forces realized that giving Germany a huge fine had been a mistake, and thus they didn't repeat that after the 2nd world war.
Inflation means your saving go to zero. Deflation means your mortgage and mortgage payments stay constant, while your salary and the price of your home falls by X% per year.