Spellcasting in a Golem?

[unseenmage]

In another thread I was provided a list of feats that would help allow a construct without class levels to benefit from Epic Spellcasting.

That list:
It'll need actual spellcasting, so use your feat to item magic to give it:
- Education
- Magical Training (Wizard)
- Planar Touchstone: Catalogues of Enlightenment
- Extra Spell Slot * a lot
- Open Minded * a lot

This should, technically, give you up to 8th level spell slots to throw around (assuming CoE gives you actual "You can cast these spells" spells.). It'll be expensive, but noone ever said that spellcasting was cheap. It's also incredibly iffy. To get 9th level spells, you need more detailed cheese plans. I think also this means that your spellcasting is pretty much always caster level 1. Perhaps craft a staff and give them Master Staff and Master Wand as a feat so they use their copious numbers of spell slots instead of charges. For a fake Simbul, this should be enough, as it has nowhere near the raw power of an epic spellcaster, but it does have the appearance of it.

The Epic Spellcasting idea is a no-go but the possibility of granting Effigys and Golems spellcasting by imbuing a few feats intrigues me.

So my question is, what array of feats can grant spellcasting up to 9th level spells to creatures without class levels?

Additionally an explanation would be helpful as well as I'm not understanding how Magical Training, Extra Slot, and Planar Touchstone:Catalogues of Enlightenment are totalling up to 8th level spells in the first place.

Thanks regardless Playground.

[Harrow]

Magical Training gives you 0 level spell slots. Extra spell slot gives you one more spell per day of the level under the highest level spell you can cast. From here, you use shenanigans to use a 0 level spell slot to cast 2 level spells, so you can take Extra Slot to gain a first level spell slot. Then use the same shenanigans on your first level slot, take Extra Slot a second time and gain a second level slot. Rinse and repeat.

The problem is that, even once you get a 1st level spell slot, you don't have any first level spells to prepare in it. I guess Catalogues of Enlightenment I guess are supposed to be used for that, but I'm not so sure how that works.

[unseenmage]

Magical Training gives you 0 level spell slots. Extra spell slot gives you one more spell per day of the level under the highest level spell you can cast. From here, you use shenanigans to use a 0 level spell slot to cast 2 level spells, so you can take Extra Slot to gain a first level spell slot. Then use the same shenanigans on your first level slot, take Extra Slot a second time and gain a second level slot. Rinse and repeat until you have 9th level casting.

Okay, that makes sense enough, except; what shenanigans exactly? Are they part of the feat build or are they spells or what? Sorry if this is posted elsewhere but I'm not finding it with the Google-machine.

[Harrow]

Heighten Spell and Metamagic School Focus would work. There are all sorts of ways to reduce metamagic, but this is the only one I can think of useful for giving a Golem or effigy casting through feats.