So upon further reading. Turns out becoming undead will not allow this to work. Tainted metamagic says you have to have a constitution score in order to use it.
But alas I found a cheaper, easier method to do it.
level 1 Sorcerer.
Level 2 Cleric
Level 3 Tainted Sorcerer.
Feats that make it...
Hello, I am making a new sorcerer character. Was looking into doing a metamagic build with one.
I thought it might be fun to do make it a Tainted Sorcerer. I was trying to lower my metamagic costs with feats. Then realized, I could just become undead, or find a way to negate constitution...