I started using it a lot after reading many of the Posts and AARs on the board. In fact, it is one of the main things I look for in a nation when I start (how I would use the nation to get up to cast Acashic as fast as possible) and one of my first priorities I have in a game along with acquiring provinces as fast as possible.
Since I don't use a rainbow pretender and like to keep my mages doing research instead of running around searching, I use the spell almost exlusively to get my gem income going. Once in a while I will have my pretender and/or the priest/mage travelling with him to search while resting and waiting for more troops, but for the most part I rely solely on Acashic Record.
I like to have mages of all types, either through choosing a nation that allows random choices, or finding wizard or other random choice site provinces. I like to be able to forge items of all types, depending on the situation, and summoning of many types. I don't see any way I could research fast and find sites as fast as with casting Acashic Record the way I like to play. Plus, it even finds the hard to find sites that require a higher mage skill to find. I even got an extra fortress and temple in my most recent game this way through finding a site that gives you one. That was a first for me and a nice surprise
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