-2 unnamed from dark companion
-2 unnamed from aura of despair
-2 unnamed from aura of sadness
-2 from being sickened (sickening strike)
-2 from being shakened (terrifying strike)
-4 from Insane Defiance (elder evils feat, take 1 wis damage to redirect a mind affecting spell you cast on you self to someone else)
And on the other side of Saves, theres DC boosting as well.
Snowcast (frostburn): Adds the [Cold] descriptor to all spells you cast if you have snow.
Eschew Materials (core): Never run out of snow, even in the desert.
Draconic Heritage (dragon magic): Take any dragon that is [Cold] based for the other draconic feats.
Draconic Aura (dragon magic): Up to +4 to the save DC of any [Cold] spell (scales by level).
Draconic Power (complete arcane): +1 to the save DC of any [Cold] spell you cast.
Cold Focus (frostburn): +1 to the save DC of any [Cold] spell you cast, stacks with all the other focuses.
Greater Cold Focus (frostburn): +1 to the save DC of any [Cold] spell you cast, stacks with all the other focuses.
Icemail Armor (item,
online): +2 to the save DC of [Cold] spells you cast.
Of course you have no feat room with the above. In fact you'll have to take two flaws and dip into sorcerer to get them all and still have room for a metamagic feat but you don't really need them all. Well, maybe you don't...
-10 on their save, +9 on your DCs, assuming 34 wisdom that's like trying to beat DC 41 + spell level (45 if mind affecting).