Him and Snake are alot heavier then they look. Take alot more to kill them. Oh, and Ballade your Dedede is annoying, not to mention Akamaru's ZS.
Trying to main Dedede more than the others. Granted I'm good with them, me and Dedede seem to have some kind of sync going on (I was insanely great as him when I played as him for the first time. Great for a first-timer with a character though). Sadly, my game's a [tornado fang]ing glitch hot spot, and I can't actually train as him against lv. 9s because they'll get the Dragoon and the Smash ball at the same time, have the magical accuracy to hit me (or team up on me and hold me while they fly in for the kill), and then once I'm done reviving, they hit me with their Final Smash. I seriously wish I was joking when I say it's gotten so bad, I HAVE to keep the level below 6 in order to actually stand a chance. I either get ganged up on, or glitched into losing status.
And yet, somehow, he's on the "Top Tier" of professional tournaments.
Personally, I prefer the air don't get it.
The guys who make up those tiers just do it so they have an excuse when they lose.