It looks like the 8th mastery for Rus civ (‘Day and Knight’) is outdated, because it requires the player to “Defeat 15 enemies with Early Knights in the Feudal Age (II)”, but apparently there are no more Early Knights for the Rus civ any longer.
I’ve been away from the game for a couple of months, so I tried having a quick look in the last patch of the game and in the forums here, to see if there were any mentions of this issue or of the fact that Early Knights were removed, but to no avail… I found nothing.
In any case, there it is: the Rus mastery is not possible to be completed because of the removal of Early Knights.
Images to illustrate my case:
LMAO that’s the issue of staying away from the game for so long 
My brain just thought of simple knights as persons…
Thank you for the reply! Imma get to finishing this mastery right now
1 Like
no problem, it can happen sometimes, Good continuation of the mastery 