The Sid Meier's Civilization VI: Byzantium Gaul Pack for Nintendo Switch adds two new civilizations, Byzantium and Gaul, each led by unique historical figures. Players can take command of Basil II, utilizing the Byzantine Empire's religious and military strengths, supported by the Dromon Ship and Tagma units. This expansion enhances the strategic depth of the game, allowing players to pursue both conquest and cultural dominance in their gameplay.

In addition to the Byzantine Empire, the Gaul civilization is now available, led by Ambiorix. This civilization emphasizes military flexibility, supported by the unique Oppidum district that boosts culture and production. The new pack encourages diverse strategies and offers fresh gameplay experiences, making it a valuable addition for fans of strategy games looking to expand their empire-building tactics.