I think I'm right when I say that he was temporarily given super powers by Jor-El so that he could bring home Clark, who had been infected by red(?) kryptonite and had run away to the city. The stress of having the powers whilst still human caused his body to weaken and eventually he had a fatal heart attack on the farm
You're right in saying the above all happened, that was the... Season 3 storyline. Papa Kent died back in season 5 when Clark went back in time to save Lana. In a very LOST fashion, the universe course corrected to make sure someone died. Instead of Lana being hit by a car, Jonathan's heart gave out after a fight with Lionel Luthor.
He'll probobly be back in dream fashion or, considering how season 7 ended, mabye some Kryptonian Heaven

I'm guessing that he'll only be back for that episode, although conisdering Season 10 is Smallville's last, he may be back in the Finale in true TV fashion

I have also heard that the writers are interested in bringing Martha back which could be interesting... Mabye we'll see Jonathan through her?
Keep It Chillin'
LOST Cast I've Met...
Andrew Divoff (Mikhail), Frederic Lehne (US Marshall),
Francois Chou (Pierre Chang), Adetokumboh McCormack (Yemi)
Thats me in the middle.


Spoiler TV Expert for Smallville and Doctor Who - Feel Free to ask me anything
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