Will people stop saying that Shuckle is a good wall. He isn't. His most popular set, Chesto/Rest is crap. One use of that item and then he's on his own. Has to set up Contrary/Shell Smashes just to have enough bulk to survive with that abysmal HP stat. And even then, Critical's ruin him completely. (murphy's law, set up with Shuckle and the opponent suddenly has a 100% Crit Rate). His only means of offense are Infestation and Toxic, which means any Steel type walls him hard. Taunt wrecks all of his movesets, unless Shuckle is under Trick Room which only works in doubles.
Don't get me wrong, I love Shuckle and I enjoy using him in my doubles team. I have him set up Power Trick while my team mate uses Trick Room (unless the opponent has a Flincher/TR user), and then decimate with Rock Slide. Nothing more brutal than STAB Rock Slides from his Power Tricked Attack stat.
BUT, that's a gimmick, and not wall-ish in the slightest. He just relies on his bulk to survive that first turn. In singles, he is a completely terrible wall. Those gargantuan defenses cannot help his piss poor HP, awful offenses and laugh worthy Speed stat. His terrible movepool cripples him further sadly.
Official Tobi of all Naruto boards- "I'll show you the truth!!" --Sazh > Tobi > everything else > Yuji Kaido--