Reddit reviews My Little Pony: The Daring Do Adventure Collection: A Three-Book Boxed Set with Exclusive Figure

That's the Daring Do Adventure Collection.

Just in case anyone wants to know where they can buy it, Amazon has it. I learned a few new things about the show that wasn't even mentioned in the show (like the names of the Wonderbolts [one of them is Surprise!] and that the first two episodes were originally going to span across a whole season.) The book is about 1/2 episode recaps, but it gives some great insight on the show (such as why they only redeem a few villains or why the people may enjoy the show.) I'd recommend buying it if you have money to kill.

Oh, and soon, two more books are going to come out.

My Little Pony: The Journal of the Two Sisters: The Official Chronicles of Princesses Celestia and Luna

My Little Pony: The Daring Do Adventure Collection: A Three-Book Boxed Set with Exclusive Figure

I can do ya 3 better.

http://smile.amazon.com/gp/product/0316406120

Also, there's some Daring Do books that have been published. The first 7 books sadly remain fictional, including Sapphire Stone (book 1) and Ring of Destiny (book 5).

Pay attention and the show (also books and comics) have lots of dark lore hints, mostly in the background and between the lines.

That said nothing in the show references "a previous race", the cities being horse puns is for the sake of puns in the show. A planet being called earth is neither here or there. Since Earth is an old Greek word for dirt, to put it simply. MLP is heavy on historical and ancient design and lore. You could argue they should have a different name. But then it being in a human language and them calling dirt... dirt makes it moot. Earth is Earth since it is dirt.

That said, a little drawing in the two little Cakes room, at some point shows small drawings of "human figures" but that could mean so many things from artists in-jokes to fantasy (like our Unicorns), or even other bi-ped races on the planet.

If your likin lore, the comics are cool if not high octane that "stretches believability but doesn't really break canon on almost all plots (some might break on a personal level or much later in the show some might not "fit") but adds lots of extra story.
A more serious and closer to the show type stories are the G.M. Berrow books, they are kid looking on the cover but fairly serious and show canon friendly in actual reading. She also did 3 official Daring Do books that are also very good made by her under the A. K. Yearling penname: https://www.amazon.com/Little-Pony-Adventure-Collection-Three-Book/dp/0316406120/ref=sr_1_1?ie=UTF8&qid=1542945168&sr=8-1&keywords=daring+do

Amazon also has the 3 separate books for a little cheaper then the box set.

8 Used from $48.50 24 New from $48.39

How does that work when it was just released today?

Amazon Link

Here's the Amazon.com listing for the book set. Holy cow, that font size is big. 624 pages are advertised, but this can't be more than a few thousand words.

It's the boxed set for the new Daring Do novels!

Amazon has a few choices. I personally got this set and I think it’s a fine addition to my collection.

http://www.amazon.com/gp/aw/d/0316406120