One of the top paid 'complete projects' on AssetStore, TowerDefenseToolKit (TDTK) is a an easy to use and flexible Unity game engine coding framework designed for construction of TowerDefense(TD) game. The aim of the toolkit is to allow as many variant of TD game as possible. It's designed with integration of custom asset in mind. The toolkit is written with non-coder in mind...
TowerDefense ToolKit v3.0