Greninja my second character and I'll use him to scout my opponent's abilities and play style. I really love his Water Shuriken. It comes out so fast. It applies so much pressure and control, I personally think it's Greninja's best move.
Sometimes. I find myself growing more as a player with Ike than I do other characters, so I play them less frequently. I have a tendency to favour heaving hitting characters that can survive to extremely high percents. Greninja and Little Mac don't that much staying power, especially compared to Ike. I still enjoy play playing Greninja and I play him as my second character, but Little Mac, and to a lesser extent Greninja, have both become pocket character for me.