I have been using totodile ever since I got her and is now at level 100 as a feraligatr. Pairing it up with meditite and serperior at the moment for a quick sweep with the sure hit, sure crit 200atk mega kick. All of them have their pros and cons, synergy is key in this game.

Other 5 stars I have is a houndoom and treecko, both are great too. Just that my personal preference has always been totodile and squirtle (hopefully comes into the game in the future)