I want to release my game on several platforms however the title I really want to use is already being used by an individual. The creator made their game through a "Game Jam". This is when one or multiple people create a small game under a short time period. The creator is not an established company. After looking at their store page on steam and on the website in which the game is advertised on, I can't seem to find any instance of a TM, R, or C reserving the title of the game.
I don't know a whole lot about trademarking, registered trademarking, or copyrighting property and I want to know what actions I need to take to be able to legally use this title and have them remove theirs. Can I simply use an unregistered trademark it or do I need to register the title?