This could be an ultimate option on spare times, because the TD platform has many fans among people. The player could be prompted about aditional download,if he wants to play that. So, the initial apk size of the game wont be changed, and the player will recieve only the game itself at beginning.
I'm not a fan of making money using games, so I leave that part to you.
Some features: -king and queen can be used as heroes in different parts of route.
-The prize could be some resources.
-You will begin with basic level 1 towers and can upgrade them gradually.
-Infantry and air units can be used when you called for help by giving some resources away to slow down the attackers and give towers more time.
-Attackers could be goblins in different shapes, and many other units.
