Even within the Septian Church, access to the Apocrypha are limited; only members of the Gralsritter are allowed to browse them. One of these is the Book of Ladder (ラダー記), which describes the Pleroma Grass as a mysterious flower that can be interpreted as a good omen or a bad omen.
A second text is named as one of the apocrypha in Kuro no Kiseki- The Book of Ezer (エゼル記). Its contents are first mentioned in Trails in the Sky the 3rd with a passage called 'Disaster Unleashed' "That brief moment of hesitation was all it took to spawn a great evil. It crawled through the fields, ran through the hills, and spread disaster in the skies above."" Book of Ezer verse 2.
The Book of Ezer is described a text that drains the very soul of those who read it without due protection. Rion Balthazar implies the D∴G cult forced it's child experiments to read from it, including Van Arkride.
- Ries Argent mentions a Book of Genesis which contains a record about Primal Grounds. Due to the knowledge of these being secret to the public, it is possible that this is another apocryphal text.