How about a Dwarf Transmuter Wizard built around tripping that uses polymorph to turn into a Treant or Annis Hag? At level 7 with 18 int you could do it for at least 3 combats/day. Eventually, on top of Expertise, Imp. Trip, and Combat Reflexes (your 1st, 3rd, and 6th level feats), you'll want EWP (Spiked Chain). Might consider even dipping Fighter at some point since you're more about being a big, stupid fighter than being a caster, but starting at 7 you need to stick to wizard just to start the game w/ the polymorph schtick. Int honestly doesn't need to go much past 18, by all means pump con up to overcome your d4 HD. Should be pretty easy with decent rolls or moderate PB to have at least con 16 int 18 by level 7, even without a +2 item. If MM races are available, could do Forest Gnome instead of dwarf if you prefered, just to be a little weakling that rages and becomes a big, hulking mass of destruction.
I'd suggest Wiz 7, maybe go up to wiz 8 (boosts BAB; another use/day of polymorph), then Fighter 1 to get EWP, then into Eldritch Knight.
