Got it:

King Vendrick

Half-Ogre Gheden

2 Fighter/3 Barbarian/10 War Hulk

Assume 36 point-buy
Str: 46
Dex: 16
Int: 1
Charisma: 2
Wis: 8
Con: 18

Spoiler: DS2 Spoilers
Vendrick's exile and slow transformation into a giant from Nashandra's meddling caused him to hollow and lose his sanity and mentality, but his strength and reflexes stayed as sharp as ever.

1:Dodge, Power Attack, Cleave, Monkey Grip
2:Improved Bull rush
6:Awesome Blow
9:Large and in Charge
12:Combat Reflexes
15:Karmic Strike

He has a permanent Enlarge Person cast on him, and wears strongarm bracers. Thusly, he wields a Gargantuan greatsword in one hand or a Colossal greatsword in two. Note that if someone rules that Monkey Grip and Strongarm Bracers donít stack, then get rid of one or the other and use a slightly smaller sword.

This build is just knockback cheese. When power attacking, you can hit someone and bull rush them as well as Awesome Blow, and this gets to apply to AoOs as well. This also works for Mighty Swings too. If an enemy comes near you, you get a hit like this again.

I set this at 15 since I couldnít think of any other classes for flavor, although you could probably fit in 7 levels of another class with full BaB and bump down War Hulk to 8 to get Robilar's Gambit for more abuse.

CR 17, I believe.