while I agree that shapechange is awesome, and one of the most broken core spells printed; it has its limits and does not "win" every time. If you are playing D&D to "WIN" D&D, you're doing it wrong; there is no "winning" D&D, its a role-playing game intended to be a storytelling tool and to get people together to have fun with their imaginations - not a competition. The actions you take on your turn determine victory in combat, and the ones you do outside combat determine success or failure according to the DM. Now, that build is cool on paper when you ignore all the crunchy details, like 10 ranks in Knowledge (the planes) with only 1 class giving 2+int mod skill points for 1 level having it as a class skill that your build takes as its 7th class level; or the ability to cast dismissal or dispel evil. When you provide a build, CJ, and they ask you for details, INCLUDE THE DETAILS please. Otherwise you aren't contributing. Here are some baseline details for CJ's suggested build-
2 flaws (i suggest Weak Willed and Vulnerable), Human Paladin 2 / Sorcerer 4 / Spellsword 1 / Abjurant Champion 5 / Sacred Exorcist of (insert good deity of magic that also happens to sponsor paladins) 8
Str- 10, Dex- 10, Con- 14, Int- 10, Wis- 12, Cha- 18; add all level-up points to charisma (physicals besides Con left low since you won't be in "human" form for pretty much the whole game - they get replaced with bigger numbers; however your hitpoints are still based of your original constitution score)
Feats- fl- Combat Casting, fl- Education, human feat and all other level feats as you desire (if you don't take Education, skill ranks for knowledges become crunchy)
Skill Points- 1st- Knowledge (religion 4), Knowledge (arcana) 4, Knowledge (the planes) 4; 2nd- +1 to the three knowledges; 3rd- +1 to the three knowledges; 4th- +1 to (the planes) and (religion), +1 Concentration; 5th- +1 to (the planes), +2 Concentration; 6th- +1 to (the planes), +2 Concentration; 7th- +1 to (the planes), +2 Spellcraft; 8th- +3 Spellcraft; 9th- +3 Spellcraft; 10th- +3 Spellcraft; 11th- +3 Spellcraft; 12th- +1 Spellcraft, +2 Concentration; 13th- +1 Spellcraft, +2 Concentration; 14th- +1 Spellcraft, +2 Concentration; 15th- +1 Spellcraft, +2 Concentration; 16th- +1 Spellcraft, +2 Concentration; 17th- +1 Spellcraft, +2 Concentration; 18th- +1 Spellcraft, +2 Concentration; 19th- +1 Spellcraft, +2 Concentration; 20th- +1 Spellcraft, +2 Concentration (end up with max ranks in spellcraft and concentration, and all required ranks for PrC's)
Equipment- take items that you can easily see to be wearable by whatever forms you want to assume with shapechange an make sure they buff your stats, ac, saves, etc.
Spells Known- at first level, pick shield as a spell known, and at 12th level, you have to take dismissal as a spell known to get into Sacred Exorcist, other than that you can trade out spells according to sorcerer whenever you level up, but you need to retain at least 1 abjuration known and dismissal or you lose access to some of your PRC features.
If you want another build suggestion I'll pm you the details for it but basically its Human Sorcerer 10 / Incantatrix 10, has base attack of +20, full spellcasting, tons of metamagic feats.