Sniper Rifles are God-Tier

I must worship it. Subverting the cliché of shotguns and machine guns being high-efficiency in zombie defense games, sniper rifles are performing better than expected. The bullets inherently have penetration, so you don't need to invest as much in skills for clearing fields, like additional penetration or ricochet. You can cover the lack of angles with 'Punishment' and 'Encore', and if you take 'Fragment Eruption' and focus on raw attack power, you can just plow through fields. The sniper rifle's unique bullet-to-attack ratio also deals good damage to bosses.