Just a random observation...
I was really surprised when I realized that the wish spell is not part of the 1974 LBBs.
The first time the M-U spell appears is in Greyhawk Supp 1.
The LBBs do have a ring of three wishes in Book 3, but that's it.
It goes to show how much GH really influenced what we see as "OD&D" when in reality, GH was a huge change from the original game.
I had always just "assumed" that wish had been there from the beginning, but NOPE
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There are other bits of just sticking to the LBBs and not including GH/BM/etc that really make it stand on its own with some unique bits.
I *LOVE* that clerics need spell books.
It totally makes sense as prayer book, hymnals, or just a bible-like book.
A ton of game opportunity in a 4th level cleric needing to get their hands on a 2nd level prayer book and they're far away from one of their temples, but a different temple is nearby.
Now I get why 7th clerics had to declare Law or Chaos
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And on top of that, with the (possible) misprint of the cleric spell progressions in OD&D, declaring Law/Chaos at level 7 once clerics get 4th level spells and prior to them getting top 5th level spells at level 8 - the whole spell book thing for clerics is just awesauce layered on that.
Here's an interesting discussion on cleric spell progression and an error that may have just propagated through time...
https://odd74.proboards.com/thread/16263/cleric-spell-progression
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FWIW, I shifted my progression to differ from the LBBs based on this discussion:
7th 2/2/2/1
8th 2/2/2/2/1
9th (goes back to LBB values) 3/3/3/2/2
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