Long ago, Star Swirl the Bearded traveled all across the pony realm. He visited lands that none thought existed, visited creatures of variety races, and discovered magic that even the gods would fear. He recorded his findings-75 long years worth of it-into a journal.
And now Twilight has that journal. She intends to find out what Star Swirl meant when he writes, "Ancient Gods"

Blood of Nightmares
Shining Armor was just promoted to Captain in the Equestrian Military. However, Celestia reveals to him that Equestria has been fighting a secret war against a powerful race that many thought were legends: Vampire Ponies. Shining Armor soon faces a mountain of problems with the new recruits and the growing threat.
And then he engages combat with the one pony that Celestia forbid him to not, leaving him incapacitated.

Astral Fang and Blood Star are twins, but they do not know it. Raised on opposite ends of the Kingdom, Blood and Astral think that all is well; until a murder happens before both of their eyes. As Blood and Astral investigate, they both realize that something dark is brewing in Nocturnaque. Something that dates back to the start of the Current King's rule….
And what does their real parents have to do with it?