Crystal Tales Tactics Guide is a spoiler document with everything you need to know to complete the game (including all endings). It's the easiest way for you to unlock the whole content of the game (including Steam Achievements).

This DLC contains a pdf document FULL OF SPOILERS about Crystal Tales Tactics.

To access the document, you need to go to:

Location:
C:\Program Files (x86)\Steam\steamapps\common\Crystal Tales Tactics - Echoes of Libertas War\Crystal Tales Tactics - Guide.pdf