Grond (battering ram)
Grond was a battering ram, used by Sauron's forces to destroy the Great Gate of Minas Tirith during the Battle of the Pelennor Fields. It was named intentionally to evoke the memory of the mace of Morgoth, the "Hammer of the Underworld".
Peter Jackson's The Return of the King: In this film, ram took the shape of the whole wolf's body, instead of just it's head. There are inscriptions on it. Grond appears earlier in the battle than in the book.