Have the shooting game pit you against unrealistically tough enemies where the game is rigged to cheat against you. Make the game microtransaction-supported, where the only way to get more ammo is to spend "gems" at ammo dealer shops. The gems are, of course, only available at the Cash Shop, $.99 apiece, a box of 10 for $15.99, a chest of 100 gems for $199.99, or a trunk of gems for $999.99.
If you die during the game, you must wait 24 hours to restart the game or pay 10 gems to instantly resurrect yourself and continue your game. You must also pass through doors that can only be unlocked by keys using a very slow key-making machine. The keys will either take 4 hours to finish or will cost 5 gems.
Oh, and the game will only be available on smartphones and tablets, and the artwork will look like a cross-eyed third grader drew the characters.
