When you go to purchase a follower crystal in the shop it states “A random Crystal belonging to any one of your current Followers to help you Evolve them.”
This is not the case. I have purposefully not finished the story and therefore not unlocked all the followers because I want better odds at some Northelm crystals. I now have 3 Darkhunter crystals and have not unlocked Darkhunter yet.
I am 99% sure I have got at least one of those crystals from spending wooden marks too. The text there is also the same.
As luck/bad luck would have it. On the left this is my 1st Northelm crystal after many months of buying follower crystals. I now have 1 out of the 5 I need until I can have a legendary size inventory of 140
(I have all the crystals possible from the sidequests)
