Greninja for me. Water/dark type ended up being a great combination! I didn't think I'd like him at first, but I picked Froakie anyway and was NOT disappointed. I've always had a bias for the water types xD
Favorite pokemon from Kalos is Greninja and Malamar. Greninja is awesome and Malamar is fun. Even if howto evolve Malamar is bull. They should of had an ingame note or something. Sad that the older gens were better at explaining special evolutions better then the new games.
Stll Mala mala contrary is fun and the dark/psychic is fun too. I always name mine clopin because topsy turvey day!! Besides having a mala out when you fight a kanga is great cause topsy that boosted power punch.