Lana's Birthdate
Green skull
No, Lex was not mentioned in season 10 nor did he appear there.
He can shoot missiles, fly with his jet shoes, and use a flamethrower in his green and purple power suit. I have also seen him in other suits but I think the green one is his main suit.
The actors that returned in the final episode of Smallville are Michael Rosenbaum which the one that plays Lex Luthor, John Schenider which is the one that plays Jonathan Kent and Annette O'Toole which is the actress that plays Senator Martha Kent.
Lex Luthor
no
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Dr. Helen Bryce was the one who was responsible for the attempted death of Lex Luthor in Season 3 of Smallville.
No, Lex was not mentioned in season 10 nor did he appear there.
Yes, Lex Luthor returned in the last episode of Smallville which is titled "Finale."
Lex Luthor - Smallville - was created in 2001.
John Glover did not leave Smallville of his own choice the writers of the Smallville series had made the decision to write him out by making it so that his own son; Lex Luthor would murder him however the writers later brought John Glover back in Season 10 as Lionel Luthor but as Lionel Luthor from another alternate reality in which the Luthors were the one who had found and adopted Clark Kent and therefore became Clark Luthor.
Kitty Kawolski
It's episode 19, season 6. Have fun!
Lex is just a nickname for Alexander Luthor in Smallville.
Season 7 was the last season for Michael Rosenbaum and John Glover who respectively portray Lex Luthor and Lionel Luthor.
In the last episode of Season 10, Lex Luthor lost his memory as a result of Tess Mercer touching him with neurotoxin which was poison that resulted in Lex losing all of his memories prior to Tess putting the neurotoxin on his left cheek.