Weak to none of those types:

Hitmontop
Item: Leftovers
Ab: Technician
EVs: 252 Sp. Def, 200 HP, 56 Atk
Nature: Careful
*Bulk Up
*Bullet Punch
*Mach Punch
*Rapid Spin/ Fake Out (depending on the rest of your team)

Hitmonchan
Item: Leftovers
Ab: Iron Fist
EVs: 200 Sp. Def, 200 Atk, 108 Speed
Nature: Careful
*Bulk Up
*Mach Punch
*Bullet Punch
*Ice Punch/ Rapid Spin
Problem is that that Hitmontop and Hitmonchan have no reliable forms of recovery outside of Rest, and both have a mediocre Defence.

Rotom
Item: Leftovers
Ab: Levitate
EVs: 252 Sp. Def, 252 HP, 4 Speed
Nature: Calm
*Pain Split
*Will-O-Wisp
*Thunderbolt
*Shadow Ball
I would suggest Rotom-Wash (best Rotom typing), but it's OU, and Rotom-Heat is weak to Rock & Water. Rotom also has no reliable form of recovery, since Pain Split is situational.

Mismagius
Item: Leftovers
Ab: Levitate
EVs: 252 Sp. Def, 200 HP, 56 Sp. Atk/ Speed
Nature: Calm
*Calm Mind
*Shadow Ball
*Pain Split
*Hidden Power Fighting
Again, situational recovery.

Cofagrigus
Item: Leftovers
Ab: Mummy
EVs: 252 HP, 200 Sp. Def, 56 Def
Nature: Calm
*Calm Mind
*Will-O-Wisp/ Haze
*Shadow Ball
*Hidden Power Fighting
^ The mother of all walls. I know Cofagrigus has a base 145 Def, but a 105 Sp. Def isn't shabby.

Dusknoir
Item: Leftovers
Ab: Pressure
EVs: 252 Sp. Def, 252 HP, 4 Def
Nature: Calm
*Shadow Sneak
*Will-O-Wisp
*Pain Split
*Shadow Punch/ Seismic Toss

Spiritomb
Item: Leftovers
Ab: Pressure
EVs: 252 HP, 252 Sp. Def, 4 Def
Nature: Relaxed/ Impish
*Will-O-Wisp
*Pain Split
*Shadow Sneak
*Foul Play
Other Pokemon that are hit by those moves neutrally (which come to mind) are Kingdra, Muk, and Ampharos, though neither would make an especially good wall.
Other options

Milotic
Item: Leftovers
Ab: Marvel Scale
EVs: 252 Sp. Def, 252 Def or HP, 4 Speed or Sp. Atk
Nature: Calm
*Scald
*Recover
*Haze
*Toxic/ Dragon Tail

Slowking
Item: Leftovers
Ab: Regenerator
EVs:128 Sp. Def, 128 Def, 252 HP
Nature: Calm
*Scald
*Slack Off
*Fire Blast
*Thunder Wave/ Psychic

Umbreon
Item: Leftovers
Ab: Synchronise
EVs: 252 HP, 4 Def, 252 Sp. Def
Nature: Careful
*Wish
*Heal Bell/ Yawn
*Foul Play
*Protect

Bronzong
Item: Leftovers/ Light Clay
Ab: Levitate
EVs: 128 Def, 252 Sp. Def, 128 HP
Nature: Relaxed/ Calm
*Reflect
*Light Screen
*Hypnosis/ Stealth Rock
*Gyro Ball

Scrafty
Item: Leftovers
Ab: Shed Skin
EVs: 252 HP, 4 Atk, 252 Sp. Def
Nature: Careful
*Bulk Up
*Drain Punch
*Crunch
*Rest
My favourite set for Scrafty, but Shed Skin isn't reliable.. in any case, this set sees a tank Scrafty that will be able to pack a punch with some set up.
Those are my ideas for a special wall. In any case, Ghost, Electric, Poison and Fighting are the only types that are hit by those moves neutrally. I might have missed some dual types that get neutral damage...