Your an Incantatrix and your Spellcraft check only hits 60 in epic? My god. I have an incantatrix that hits 60 at level 18. And thats before I use Moment of Prescience to get +20 on the check.

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But anyways. There are 2 basic approaches to epic casting

First up: Rituals
You create an Epic Spell that permanently summons a Couatl.
The DC pre mitigation is 150 (30x5).
Increase the Casting time to 10 minutes (-18).
Increase the Casting time by 86 days (-132).
The spell now is free to create and has a final DC of 0.

The Draw back of this spell is the time required. If you have used arcane genesis to get your own personal demiplane with a much faster time trait that isn't really a problem but otherwise I recommend the following:
Hire 15 level 9 casters to sacrifice 1 5th level spell slot per casting. And keep the 10 minute casting time. At level 21 you should be able to cast 2 Epic Spells per day.

So day 1 you hire 15 level 9 casters and gain 2 Couatl's (which cast as level 9 clerics meaning 5th level spell slots).
Day 2 you hire 13 casters and gain 2 more Couatl's. And so on. By day 8 you don't need to hire any more casters.

Repeat the above until you have 30 Couatl's (so 15 days worth of casting).

Now you make your next epic spell. This is like the one above but permanently summons a solar instead of a Couatl. You need 30 Couatl's to mitigate the DC down to 0 with a 10 minute casting time.

Every 10 days of summoned solars allows you to mitigate away another 340 points of the spell craft DC. After 30 days you can mitigate away 1,290 points of the spell craft DC.


Now make whatever spells you want and mitigate away the costs. Permanent buffs are very nice.

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The other way (thats less cheap) is to make Fortify Intelligence spells and just stack them (you get +1 spell craft for every 2 points of Intelligence).

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Now let's assume that you did the ritual thing.

Some good spells are the following:
Immunity to all Spells:
DC 970 pre mitigation (use the Ward seed and don't choose the radius option). This includes immunity to all epic spells as well.
Resistance to all Normal attacks:
DC 1,290 pre mitigation (again using the ward seed). This gives you resistance to piercing, bludgeoning, and slashing damage of 125 points per turn.
Sonic Bolt:
DC 1,290 Pre mitigation. This uses the energy seed and gives you the spell like ability to create a Sonic Bolt that deals 633d6 damage (range 300 feet, reflex half) at will. But we only need 300d6 damage. Which allows us to add 312 to our caster level check to beat SR and change those d6's to d20's.
Epic Armor:
Use the armor seed and you can gain +24 AC of one of the nice types (Deflection, Luck, Divine, Profane, insight, etc). Get a few different versions (1 for each type) and you can end up with an AC of 120 just from this spell.


Those are just some ideas.

But the real power comes with the Origin of the Species spells. You make a creature that can breed in like 5 seconds and that has every possible ability you can think of as an Ex ability, including the ability to instantaneously mind switch with 1 willing person. You then make it extra specially loyal to you and order the mind switch. All the sudden you are in a body that makes the gods whimper in fear. Although for the really good ones you need to be able to mitigate a DC of around 20,000.

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No I am not suggesting that you actually go out and use Epic magic like this but that is how you do the uber broken Epic casting. And even this stuff (besides the Origin of the Species) pales beside some of the stuff you can do (I have moved stars around before.).