I hate people who lie about the code in the title of their world just to attract more players. If you don't want to share the code, never imply this, not even in the actual world with the all famous "C: ". Not all players are trolls and you are basically mocking everyone with your lies. If you lie that easily about such a small thing, do you always lie ?
Wouldn't it be cool if there would be an option in which you have to kill the adventurers in a limited number of days ? And where the dungeons would already be built and you would just have a limited number of traps and monsters to place on each level ?
 "Zombie Splatter")
 "Bubble Tanks 3")
 "The Sandbox")
 "Everybody Edits")
 "Cubelands")
 "Over The Border")
 "Kids Vs. Santa")
 "Champions of chaos")
 "Frontline Defense 2")
 "Langman")
 "DuBlox")
 "Dungeon Developer")
 "Infected")