I just recently purchased all of the source books and was trying to recreate one of my characters. However, the circle of spores was not showing as an option. Is there a way for me to select all of the books? Or should it be giving me access to all of them by default?

Also, as a DM I subscribe to the master tier. How do I allow my players to get access to books and/or characters I make for them to play(other than printing them out).

I'll gladly accept a link to a guide :)

Circle of Spores was in the Ravnica book. You have to have purchased that book on DDB. If you have, that book is M:tG content. In the character builder, tab all the way left to “home” look for the line marked “Magic: the Gathering Content” the switch next to it should be on (red). You should then be able to select that subclass in the character builder.

If you start a “campaign” and invite your players to join it, you can turn on content sharing, and you and all of your players will have access to everything each other has purchased on DDB. 

If you make a character for one of them, put it in that campaign and “unassign it,” and another player in that campaign can “claim” it as their own, removing it from your character roster and adding it to your own.

Thank you very much! Didn't realize it was MtG lol

Happy to help.