Lionel's funeral

In the episode "Descent" Lionel was killed by his son, Lex, after he refused to surrender the key he recovered from the Queens. Lex used a gun to shoot the glass out from a window in Lionel's office, and then pushed Lionel out of the window to imply suicide. As he did this, he said "no one will even remember your name," perhaps in reference to that aspect of Lionel's character being so unclear in earlier comics and films. Following his death, Clark discovered a Kryptonian device containing a message for him in the event of elder Luthor's death. The message affirmed Lionel's loyalty to Clark and warned him of the threat posed by the two keys. Clark mourns his passing, and goes to Lionel's grave at the episode's end. There, he takes a handful of the soil and sprinkles it on Lionel's grave while whispering "Thank You," like he had done at his own adoptive father's funeral.