Kratos story arc, along with the brilliant cinematic feel, the audio score, the action, the enemies, the puzzles, side quests that feel engaging, boss fights & the gory fights with Valhalla's creatures this game redefines action adventure genre with an open world yet limited linearity.
As you keep powering up Kratos, as you see the chemistry develop between him & his son, the dragon fights, the troll encounters, the fight with Thor, you can't help but feel awed by the unbelievable efforts put in by the game developers to create this flawless masterpiece. As a side note, the Valkyrie fights are difficult, but oh so satisfying.
God of War is an absolute beast of a game.