Honestly, no one truly knows the answer to this question as he left with no trace of anything. He never said goodbye, he never said where he was going or what he was going to do next etc. He literally just got up and left. The only sign we've had from him being active was on Facebook, in 2014. He created a post in regards to his 'big return', and released a Facebook game which was a 2 dimentional Feral Heart. Which is pretty sloppy for a 'big return'. Only, after a week or so, it became very faulty and it was later taken down. He then disappeared again. There is no accurate answer to this question, only that he left with no notice to any of the Staff who were moderating the game back then. He didn't even bother leaving Staff with the source code either, so Feral Heart could go ahead and make proper updates to the game, and possibly 'hire' experienced game developers to do so, instead of only being able to add/remove/replace things like maps/meshes/items which you could already do. As well as replace other things in general.
Sorry there is no true and accurate answer to why he left. We all just do not know.
It has been many years, I myself have decided not to get my hopes up in thoughts of him creating something "Bigger" and "Better", as FH was his Bigger and Better. The only thing I notice is that users didn't worship down to his feet whenever he was around, or not as much as they used to, as they would in the Impressive Title game. He had a lot of glory back then. Maybe he got bored of not having attention. These are just theories, but don't take my word for it. Hopefully more games like Feral Heart will arise, other than the cheapskate copies of Impressive Title. Usually made by people who do want attention/want to be worshiped in some way themselves. People tend to grow bad personalities through doing that.