Z Day: Hearts of Heroes presents the zombie apocalypse through real-time strategy, challenging players to build and defend a survivable settlement in a world overrun by the undead. Base construction requires careful planning with defensive structures, resource production facilities, and research laboratories competing for limited space. Hero characters serve as powerful military commanders who lead troops and possess abilities that decisively shift battle outcomes. Regular zombie siege events create community-wide threats requiring collective defense. Romance mechanics between hero characters provide narrative interest and mechanical benefits. The military research tree allows specialization in different strategic approaches. Z Day successfully updates classic mobile strategy formulas with the zombie theme, creating enough genre novelty to feel fresh while delivering the satisfying gameplay loop strategy enthusiasts appreciate.