>>53686131I'd say the closest thing to a legitimate competitor Pokemon has is Megami Tensei.
The main thing holding it back is that the series has very little appeal to children. The megaten fanbase looks like just the adult half of the Pokemon fanbase.
Ultimately I think any franchise that didn't start in the 80's or 90's has no shot. The advantage of having groundwork laid out for you is too big when it comes to monster collectors.
That said, I'm keeping my eyes peeled for the day Konami makes a Yu-Gi-Oh game where you get to have your own Duel Spirit. It's about the only thing that could topple Pokemon outside of GameFreak's continued incompetence.
