You can unlock a harder version of the main story by completing the game on Normal or Hard difficulty. DC Games Support Batman™: Arkham Knight on Steam Storage: 45 GB available space. Batman™: Arkham Knight on Steam
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Even years after its release, Arkham Knight rivals modern titles in art direction and atmosphere. The v.1.7 GOG version is widely considered the "Gold Standard" for archival purposes, offering the best balance of performance and content. Batman- Arkham Knight -2015- v.1.7 XATAB -GOG-