North Kingdom: Siege Castle is a three-dimensional, tower-defense game. A player places towers around castles and other positions they need to protect from enemy hordes. They position fighters, procure raw materials and improve their defenses to obtain victory.
The player chooses Campaign or Survival mode. That said, they must complete at least five Campaign levels to unlock the Survival mode.
The player places towers that features archers, wizards and other fighters. They win new warriors along with upgrade points to use to improve defense after every successful victory. Although they place towers, they must also place other structures like sawmills and mines to provide them with enough resources to place additional towers and fighters. If they have enough resources, they can install towers and fighters at any time during a battle.
North Kingdom: Siege Castle gives the player several improvement options. They can increase their attack radius, the range of wizard attacks or spells and the strength of towers. They can also make archers shoot faster.
During a battle, the player isn't restricted to waiting for an attack to end in real time. They can increase the speed of the battle by selecting the play button a second time.