Up above explains the stories and explains the information to answer this.
In Season 10 there are 5 episodes focused on the regular adventures of Clark and the gang: Homecoming, Isis, Harvest, Fortune, and Booster. Which of the 5 would u say is the best?
Homecoming: The 200th episode that featured trips to clark's past, present and future on his way to be and as Superman. Also featured the awsome return of James Marsters as Brainiac 5 this time with Bugboy and Clark's 5 year high school reunion.
Isis: As people have said not really a great episode it just featured the spirit of Isis taking over Lois fighting against Clark, Oliver and Tess.
Harvest: featured the young and evil alexander luthor before he became conner kent, clark and lois spending time together trying to escape a crazy town of people and clois s3x.
Fortune: The Hangover episode! Clark, Chloe, Lois, Oliver, Tess and Emil have a magical hangover! Its a lot of funny stuff not usually something in a lot of smallville episodes. Also its the final episode of chloe except for the finales and features a line said by chloe that referrs to the dark knight and amazon princess.
Booster: Booster Gold comes as a episode written by Geoff Johns along with 2 of the blue beatles but only one wearing the suit.
My favorite was the 200th episode as I loved every minute of it. Isis, Harvest and Booster I hated out of season 10 so definitly none of them. Fortune came in 2nd.