https://www.gamespot.com/articles/god-of-war-ps4-will-take-25-35-hours-to-complete/1100-6455531/

The upcoming God of War game for PS4 aims to be quite a bit different from the previous entries in the series. As opposed to Greek gods, it takes Kratos to a land dominated by Nordic gods and monsters; it's also meant to be a more intimate story about Kratos and his son. As the developer revealed today during the PSX 2017 opening presentation, the game is also going to be much longer than its predecessors.

Creative Director Cory Barlog announced on stage that the game will take about 25-35 hours to complete. This would make it significantly larger than the mainline entries in the series. For comparison, all three core God of War games average around 10 hours to beat.