God of War is an action-adventure hack and slash video game, it is the first installment in the God of War series and the third chronologically. Loosely based on Greek mythology, it is set in ancient Greece with vengeance as its central motif. The player controls the protagonist Kratos, a Spartan warrior who serves the Olympian gods. The goddess Athena tasks Kratos with killing Ares, the God of War and Kratos' former mentor who tricked Kratos into killing his wife and daughter. As Ares besieges Athens out of hatred for Athena, Kratos embarks on a quest to find the one object capable of stopping the god once and for all: Pandora's Box.