Fortified Swiss is an immersive RPG tower defense experience featuring a grand campaign that spans across the continent of Fromage. Vast hordes of mice have invaded due to the Mouse King's insatiable desire to hoard the most artisan of cheeses. It is up to the hero Castello to ward off these ravenous clans from eating and ransacking forts and castles throughout the kingdom’s provinces of Swissfurt, Goudare, Parmingham, Cheddardale, and Goatwick.

Fortified Swiss plays like a tower defense with RPG and RTS influences. It is up to the hero to construct fortifications and recruit workers. When night falls the hero is a powerful tool that can turn the tide of battle. A seasoned hero will fare better in battle, as leveling up grants bonuses to health.

Alongside leveling up, Fortified Swiss has a tiered crafting system. As players reach more difficult levels they will notice they are also able to craft more powerful weapons and armor. Gearing up for the fight to come is a key component of Fortified Swiss. Every item crafted and level earned is saved. This gives players the opportunity to replay levels just to craft a full set of armor before proceeding to the next level.