The existing Epic spells need some TLC and new ones can be added.
Multiple Epic Spells
You will be able to take the same Epic spell up to 10 times for multiple uses a day.
Epic Spell Save DC
3.5E uses "The saving throw against a character’s epic spell has a DC of 20 + the character’s relevant ability score modifier. It’s possible to develop epic spells that have even higher DCs, however, by applying the appropriate factor." https://www.d20srd.org/srd/epic/spellsIntro.htm#metamagicItemsandEpicSpells
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