Plain zombies are the main mechanic in ZWar. i think the game has a survival mode where you have to fight off endless waves of undead enemies and collect resources to stay alive in the city.
Step through hordes of the undead, using resourcefulness and combat skills to reclaim a city.
Clicking to move and shoot starts the action. Upgrading your weaponry is a key feature, allowing you to face tougher zombies as the story unfolds.
Most important is to focus on the mechanics of survival. Resource gathering is more important then fighting sometimes, and you must navigate through hordes of the undead.
Q: What are the controls? A: Clicking to move and shoot.
Q: What is the objective? A: Reclaim a city overtaken by chaos.
Q: What is one stated feature? A: Upgrading weaponry is a key feature.
Q: What is the main mechanic? A: Zombies are the main mechanic.