In Kingdoms of Amalur: Reckoning for the PC, PS3, and Xbox 360, you can parry an attack which will set you up to retaliate much quicker, and beat your enemies quite a bit easier.
In order to parry, you use the block button, however you have to block at the right time.
Simply holding block will not parry an attack. If you press block right as the attack is about to land on you, you will perform a parry instead, deflecting the attack, allowing you to setup a combo in retaliation.