Well...how cheese free? My usual suggestion is shitcanned, so we'll go with this :
Kell, out of curiosity, what build would you have suggested without the restrictions?
Shadowcraft Pun-ification, assuming you've read up on the capabilities of mythals (i.e. you can't die...ever...and have any spell you want at will). Easiest way is Focused Spec 5/Incantatrix 10/SCM 5, then use the Dusk Giant trick to achieve 21+ HD and a shadow miracle to use PsyRef. Pick up Epic Spellcasting, waste a cantrip on a mythal (emulated for free thanks to it being Evocation), and enjoy being cocooned in a magical force field of shadowy awesome.
That's for going all out at least