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Title says it all, really. I know about Thaumcraft, but what about the others, like Arcane Scrolls, Blood Magic, Mystcraft, and Ars Magica 2. Any help would be appreciated.
Arcane Scrolls is super easy. The
Wiki article explains the energy mechanic quite extensively. Basically, all you need to start are quills, scrolls, the Arcane Tome, some Arcane Stones, and an Arcane Pouch. The Arcane Tome is pretty self-explanatory.
Not sure about Blood Magic or Mystcraft.
I'm alright at Ars Magica 2. Basically, you want a Nexus, and that weird book thingy that explains everything.
There's also Witchery, which you didn't mention. Magic World 2 is 1.6.4, so every Witchery item/structure/mob/ritual/whatever is explained on
the wiki. 1.7.x info is still in progress.
If you want any info on specifics about Witchery or Arcane Scrolls, just tell me.