Place towers along the invasion path and guard the castle through ten waves.
Castle Guard Defense is a friendly introduction to tower defense: a single winding road toward your castle, five buildable plots, two tower types and ten waves of invaders that get meaner as they go.
Archer towers fire fast and cheap; cannon towers hit hard but slowly. Every kill pays a bounty, every tenth enemy in a wave is a fast runner, and the castle holds as long as your economy does. The whole defense fits on one screen - which is the point.
This version keeps one decision clean: where and what to build. Upgrades are planned.
Ten waves take roughly six to eight minutes depending on your build.
Every tenth invader is a runner - twice the speed, so place one tower specifically watching for them.