Answer
The Battle of Ipsus was a decisive battle in which war elephants played a pivotal role. Fought in 301 BC, the battle pitted the forces of Antigonus I Monophthalmus, the ruler of the Antigonid Empire, against a coalition led by Seleucus I Nicator, Ptolemy I Soter, and Lysimachus. Antigonus's army included a large contingent of war elephants, which he deployed to great effect against the enemy cavalry.