Does anyone know why the Endora/Agnes Morehead was not in the last season? Perhaps she wasn't in the last couple of seasons of the show-- not exactly sure; just know she was hardly seen if at all in last couple of seasons. Wondering if the actress decided not to renew contract or was ill...
Agnes was in the last season. I count at least 8 episodes. In her biography on this site, it's mentioned, "She had the foresight to put into her contract that she would only appear in eight out of twelve episodes, in order for her to be free to pursue other acting jobs, and she had no regrets about her decision to do the series".
On the Archives page here (materials used by Agnes biographer Charles Tranberg), there is a script for a Season 8 episode Agnes was to appear in - but in the acutal episode her lines are given to Reta Shaw. The page mentions that it is not known if this was due to illness or scheduling conflict.
8/26 Season 8 episodes seems like less than her other seasons, but you could check that by going through her IMBb. I have a recollection of Charles Tranberg's book discussing it.