The hammer and the anvil
From A Wiki of Ice and Fire
The Battle of the Redgrass Field was a battle fought during the First Blackfyre Rebellion in 196AC. Prince Baelor Targaryen (the hammer) led Dornish spearmen against the rear of Daemon Blackfyre's rebel army and crushed it against the shield wall of Prince Maekar Targaryen (the anvil). However, Ser Eustace Osgrey felt the singers left out much from what actually happened.