Also, think how bad will be if your game is ALSO called "Pixel Dungeon". When you refer your friends to it, they may actually download Watabou's game. You will have critical marketing problem with your game because your game title will be conflicting. Better, make a game with own name. Best - if you aim to make commercial / indie game, use a name that have domain free [as in free speech], then actually register the domain for yourself and get going :)