Royal Defense casts the player as the defender of a dwarven kingdom besieged by trolls intent on taking its territory. Its levels keep the action focused on a single screen, where the headquarters faces successive waves. That contained battlefield makes each assault a compact strategy problem: place defenses where they can blunt the incoming forces, then adapt as the attack continues.
Building and upgrading are central to that response. A location’s pop-up menu presents available units and structures, while selecting an existing structure reveals improvements. Towers and units have distinct damage, firing-rate, range and damage-type characteristics; some can also slow enemies or deal damage over time. Spells add another tool, and the game’s description says new units and structures appear as levels progress, giving the defense new options against the troll hordes.
The campaign is described as 60 progressively challenging levels across three game settings, with 17 creature types, 12 kinds of towers and structures, an extensive magic system and various upgrades. Those details frame Royal Defense as a single-player tower-defense experience built around successive, self-contained assaults rather than shared combat.
