Derfflinger and Mackensen class battlecruisers

The two Derfflinger class battlecruisers were amongst the most powerful warships to see service in the First World War.
SMS Derfflinger was the nameship of the Derfflinger class of battlecruisers, widely considered to be the best battlecruisers of the First World War. She fought at Dogger Bank and at Jutland, where she was badly damaged but survived.
SMS Lützow was a Derfflinger class battlecruiser that became the only German dreadnought of any type to be lost during the First World War.
The four ships of the Mackensen class were almost the last battlecruisers to be laid down in Germany during the First World War and contained the last such ships to come close to being completed