Five for the chapter and then five for the guide? Sounds a bit overly greedy.
Hi, these extended guides are not necessary for playing the chapters- they are more of a walkthrough and sometimes have some hints about future chapters.
They were originally meant only for high tier patreon backers, and were added here only because players asked for an option to buy them separately.
if you back the game on patreon as a Vanir tier (25$) you will get access to all the current chapters and to the extended guides.