|Appeared in||Smallville: Finale|
Lionel Luthor is the father of Lex Luthor and Tess Mercer. He also has an alternate universe counterpart that raised an alternate version of Clark that grew up to become Ultraman.
At some point Lionel discovered that Lex had instituted another project deep inside the chambers beneath the Luthor Mansion to keep himself alive after the events at the Fortress of Solitude. Through Lex's plan the best pieces of his imperfect clones would be grafted into a new body that would be a masterwork to bring Lex back to life. While almost everything had been recreated, Lex did not have a heart.
Lionel launched a plan to capture Tess so that her heart could be removed to save Lex's life. Shortly before the surgery, Tess escaped and shot Lionel in the chest.
Darkseid returned to Lionel offering him the deal that Lionel had previously turned down once more. Lionel accepted and became the vessel of Darkseid in exchange for Lex's life to be restored. In the process Lionel was killed and his body would soon afterward be destroyed in combat against Clark.
- Kal-El/Clark Kent/The Blur/Superman - Enemy.
- Lex Luthor - Son.
- Tess Mercer - Daughter.
- Lois Lane - Enemy.
- Jonathan Kent - Enemy (deceased).
- Martha Kent - Possible love interest.
- Kal-El/Clark Luthor/Ultraman - Son.
- Darkseid - Ally.
- The Lionel Luthor in Smallville: Finale is an alternate version of Lionel that found Clark instead of the Kents and escaped into the main continuity when Ultraman began to rebel against him. He was last seen being approached by Darkseid after saying he'd do anything to have the Lex of that world at his side.