"Seydlitz" participated in many of the large fleet actions during World War I, including the battles of Dogger Bank and Jutland in the North Sea. The ship suffered severe damage during both engagements; during the Battle of Dogger Bank, a 13.5 in (34.3 cm) shell from the British battlecruiser struck "Seydlitz"s rearmost turret and nearly caused a magazine explosion that could have destroyed the ship. At the Battle of Jutland she was hit twenty-one times by large-caliber shells, one of which penetrated the working chamber of the aft superfiring turret. Although the resulting fire destroyed the turret, the safety measures imposed after the battle of Dogger Bank prevented a catastrophe. The ship was also hit by a torpedo during the battle, causing her to take in over 5,300 metric tons of water and her freeboard was reduced to 2.5 m. She had to be lightened significantly to permit her crossing of the Jade Bar. The ship inflicted severe damage on her British opponents as well; early in the battle, salvos from both "Seydlitz" and the battlecruiser destroyed the battlecruiser in seconds.