For me it was a fight between Mass Effect, Elder Scrolls, and Fallout.
Fallout's lore isn't as big or as massive as the other two's. But its still full of quality. I mean Vault-Tec, the vault experiments, and The Enclave is just outright awesomely evil and disgusting that it became the game winner for me. Plus I get a boner from mostly anything post-apocalyptic.
Another honorable mention goes to the lore of Bioshock.
Fallout's lore isn't as big or as massive as the other two's. But its still full of quality. I mean Vault-Tec, the vault experiments, and The Enclave is just outright awesomely evil and disgusting that it became the game winner for me. Plus I get a boner from mostly anything post-apocalyptic.
Another honorable mention goes to the lore of Bioshock.