“Make a killing”in other languages

Same idea, different pictures

English began as American slang for a big win at gambling or on the stock market. Danish scores the cash box, score kassen, and Finnish strikes it into money, lyödä rahoiksi.

French fattens its cabbages, faire ses choux gras, already in print in the late 1400s. It often hints that the profit came at someone else's expense.