He also gets another moment in ep. 78 against Luciano and his Machine Emperor Skiel Infinity. After Ruka had unknowingly walked right into his plan and practically given him Ancient Fairy Dragon, Leo makes what effectively amounts to the card game equivalent of a Heroic Sacrifice just to get it back for her. Sure, they lose and he just about makes an actual Heroic Sacrifice, but boy does he royally piss Luciano off in the process!
Rua: I'll never let you have Ancient Fairy Dragon! I'm not a Signer, but Ruka, who has a Signer birthmark, is my pride and joy! And I'll protect Ancient Fairy Dragon, who is a symbol of that!